NVS TGT Science 2019 Shift 2 Official Paper (Previous Year Paper)

The pattern followed here is as below-:

It is addition of consecutive odd numbers in the series.

Hence, the correct answer is 105.

Let Rs. "x" be the fare of city Q from city P and Rs. "y" be the fare of city R from city P.

Then, 2x + 3y = 95 (equation 1)

3x + 2y= 90 (equation 2)

multiplying equation-1 by 3, and equation-2 by 2 and substracting, we get

9y - 4y = 285 - 180

or 5y = 105

or y = 21

putting y = 21 in equation-1 we get,

x = 16

Hence, we get fare for city Q from P as x=16, and fare for city Q from R as y= 21.

So, correct option is 3.

Assertion-: Beri-Beri is a viral infection.

It is false. Beri-Beri is a disease caused by a vitamin B-1 deficiency, so it is not viral infection.

Reason-: Vitamin deficiency causes diseases.

It is true that Beri-Beri caused by vitamin deficiency. Vitamin B-1 deficiency is the reason for Beri- Beri.

Hence, Assertion is false but reason is true.

So, correct option is 4.

‘Knife’ is related to ‘Cut’, means we use knife for cutting.

Similarly,

We use pen for writing.

Hence, Write is the correct answer.

The least possible Venn diagram is as follows-:

1. Some honest are doctors:- True (As, Doctor share some common part with honest. So we can say some honest are doctors).

2. No honest is doctor:- False (As, There is no any no relation between honest and doctor as per Venn diagram).

3) Some fair are doctors:- True (As, From the Venn diagram there is some relation between fair and doctor).

4. All fair are doctors:- False (As, From the Venn diagram we can't say all fairs are doctor, only we can say that there is some relation between doctor and fair).

Hence, only conclusion 1 and 3 follows.

A Kitten is a juvenile cat, means it is a young form of a cat.

A group of sheep in fairly small numbers sized is referred to as a flock.

Calf is the young domestic cow, means it is young form of cow.

Tadpole is a young form of a frog.

Hence, different pair is Sheep : flock.

So, the correct option is 2.

Pattern followed here is:

Hence, the correct answer is 4.

Volt is SI unit of voltage.

Watt is SI unit of power.

Ohm is SI unit of resistance.

All three terms are measuring units of electricity.

Hence, correct answer is option 2.

Given: 

The initial selling price of cooker = Rs.620

The final selling price of cooker = Rs.580

His loss increased by = 4%

Formula used:

Loss = cost price (CP) – selling price (SP)

Loss % = (loss/CP) × 100

Calculation:

Let the CP of the cooker be Rs.x

The initial selling price of cooker = Rs.620

So, his initial loss = Rs. (x – 620)

Loss % = [(x – 620)/x] × 100

The final selling price of cooker = Rs.580

Then his final loss = Rs. (x – 580)

Loss % = [(x – 580)/x] × 100

Now by the question, his loss percent increases by 4%

⇒ [(x – 580)/x] × 100 = [{(x – 620)/x} × 100] + 4

⇒ 100x – 58,000 = 100x – 62000 + 4x

⇒ 104x – 100x = 62000 – 58000

⇒ 4x = 4000

⇒ x = 1000

∴ The cost price of the cooker is Rs. 1000

Alternate Method

4% → 620 - 580 = 40

1% → 10

100% → 1000

∴ The cost price of the cooker is Rs. 1000

1. P is shorter than Q but taller than T. R is the tallest.

So there are three cases possible-:

Case 1-: R > _  > Q > P > T

Case 2-: R > Q > P > T > _

Case 3-: R > Q > _ > P > T

2. S is shorter than Q and taller than P.

So only Case 3 will remain, rest will be eliminated.

R > Q > S > P > T

So according to case 3, student who has two students taller and two students shorter than him is S.

Hence, the correct answer is "S".

The correct answer is Nagaur.

Key Points

• The Panchayati Raj system was first introduced in the Nagaur district of Rajasthan on 2nd October 1959.
• After Rajasthan, it was implemented in  Andhra Pradesh the same year.
• The Panchayati Raj system was inaugurated by then prime minister Jawaharlal Nehru.
• The first elections under the Rajasthan Panchayat Samitis and Zilla Parishads Act, 1959 were held in September-October 1959.
• It was a 3 tier governing system.

Additional Information

• The first committee to suggest the introduction of the three-tier Panchayati Raj system was the Balwant Rai Mehta committee formed in 1957
• The three levels were.
• Gram Pachayat
• Panchayat Samiti
• Zila Parishad
• ​The modern Panchayati Raj system was introduced in India by the 73rd constitutional amendment in 1992 and implemented on 24 April 1993.
• 24 April is celebrated as Panchayati Raj divas in India.

The correct answer is B D Jatti.

Key Points

• B D Jatti was not a member of the Drafting Committee of the Constituent Assembly.
• Basappa Danappa Jatti was the fifth vice president of India,  from 1974 to 1979.
• He also served as the acting president of India from 11 Feb to 24 July 1977.
• The Drafting Committee had seven members named:
• Alladi Krishnaswami Ayyar
• N. Gopalaswami
• B.R. Ambedkar
• K.M Munshi
• Mohammad Saadulla
• B.L. Mitter
• **D.P. Khaitan.**​

Additional Information

• The Drafting committee was formed on 29th August 1947,  through a resolution in Constituent Assembly.
• Dr B R Ambedkar was elected the president of the Drafting Committee in its first meeting on 30 August 1947.
• There was a total of 166 sittings of the constituent Assembly.
• The Constituent Assembly approved the draft constitution on 26 November 1949.
• There were total 389 members in the Constituent Assembly.

The correct answer is July 2019.

Key Points

• Chandrayaan-2 was launched on 22 July 2019 by ISRO from the Satish Dhawan Space Centre in Andhra Pradesh.
• The mission of Chandrayaan-2 was lunar exploration.
• The launch vehicle used was GSLV Mark III-M1.
• It had:
• Orbiter
• Lander: Vikram
• Rover: Pragyan

Additional Information 

• Chandrayaan-1 was launched in October 2008.
• It was India's first lunar mission.
• It was launched from the Satish Dhawan Space Centre in Andhra Pradesh.
• Satellite launching station, Sriharikota:
• It is a Satellite launching station of the Indian Space Research Organisation.
• It was renamed the Satish Dhawan Space Centre in the year 2002.
• Satish Dhawan was the former Chairman of the ISRO.
• The first satellite launched from the Satish Dhawan Space Centre was the Rohini 1A  in 1979.
• Arumugam Rajarajan is the current chairman of Satish Dhawan Space Centre.

The correct answer is Hyder Ali and the British.​

Key Points

• The series of four wars fought between the British and the Kingdom of Mysore in South India during the 18th century was known as the Anglo-Mysore War.
• First Anglo-Mysore War: 
• It was fought between 1767-1769 AD.
• Governor: Lord Verelst was the governor during this period.
• In the first Anglo-Mysore, the British, the Nizam and the Marathas fought together against Hyder Ali.
• Treaty of Madras: Hyder Ali wins against the British.
• A defence treaty was concluded in 1769.

Additional Information

• Second Anglo-Mysore War: 
• It was fought between 1780-1784 AD.
• Governor: Lord Warren Hastings was the governor during this period.
• In the second Anglo-Mysore, Hyder Ali, the Nizam and the Marathas fought together against the British.
• Hyder Ali defeated Colonel Bailey.
• Hyder Ali died in 1782 during the Second Anglo-Mysore War and was succeeded by his son Tipu Sultan.
• Treaty of Mangalore: The Second Anglo-Mysore War ended with the signing of the Treaty of Mangalore by Tipu Sultan in 1784.
• Third Anglo-Mysore War:
• It was fought between 1790-1792 AD.
• Governor: Lord Cornwallis was the governor during this period.
• In the third Anglo-Mysore, the British, the Nizam and the Marathas fought together against Tipu Sultan.
• Treaty of Srirangapatna: It was signed by Tipu Sultan in 1792.
• Fourth Anglo-Mysore War: It was fought between AD 1799.
• Governor: Lord Wellesley was the governor during this period.
• Tipu died in 1799 while defending the Mysore capital, Srirangapatna.
• The threat of the French to the British ended by the year 1799.

The correct answer is 64

Key Points

• The maximum number of candidates for which an EVM can cater is 64.
• The Balloting unit of the EVM has the provision for 16 candidates only.
• An EVM being used by ECI can record a maximum of 2,000 votes.
• EVMs were firs**t introduced in  General Elections held in November 1998.**​​

Additional Information

• The Indian electronic voting machine (EVM) was developed in 1989 by the Election Commission of India.
• EVMs are manufactured and supplied by Bharat Electronics Ltd., Bangalore and Electronic Corporation of India, Hyderabad.
• EVMs do not require a power source.
• Voter Verifiable Paper Audit Trail (VVPAT) is an independent system attached with the Electronic Voting Machines that allows the voters to verify that their votes are cast as intended.

The correct answer is Bajrang Punia.

Key Point

• Bajrang Punia is the first Indian wrestler who will fight at Madison Square Garden in New York.
• He was called by the American Boxing body for a special fight.
• He fought at Madison Square Newyork on 6 May 2019 in Grapple at the Garden - Beat the Streets fight night.
• He fought against two-time US national champion Yianni Diakomahlis
• Yianni Diakomahlis won the fight by (10-08).​

Additional Information

• Bajrang Puniya born in Khudan, Haryana is an Indian freestyle wrestler of the 65 kg category.
• He had won a number of medals for India some of them are
• Gold Medal in 2018 Commonwealth Games in Gold Coast, Australia
• World No. 1 title in 2018 World Wrestling Championships
• Silver Medal in 2021 Asian Wrestling Championships
• Bronze medal in Tokyo Olympics 2020.
• Bajrang Punia also clinched the gold medal in the 2022 Commonwealth Games, Birmingham U.K.
• Star Indian wrestler Vinesh Phogat bagged a gold medal at the ongoing Commonwealth Games 2022 in the women's 53kg category.
• Yogeshwar Dutt (born 2 November 1982) is an Indian freestyle wrestler.
• At the 2012 Summer Olympics, he won the bronze medal in the 60 kg category.
• He was awarded the Padma Shri by the Government of India in 2013.
• He won a gold medal at the 2014 Commonwealth Games.
• Sushil Kumar Solanki is a former Indian wrestler. 
• He carried the Indian flag at the opening ceremony of the 2012 London Olympics.
• He was placed seventh in the 2007 World Championships and won a bronze medal at the 2008 Olympic Games in Beijing.
• He won a silver medal at the 2012 Summer Olympics, becoming the first person to win two Olympic medals for independent India.
• Sushil won the gold medal in the 74 kg division at the 2014 Commonwealth Games.

The correct answer is The Equator.

Key Points

• The Equatorial regions receive the maximum energy from the sun over the year.
• As the equator lies at 0° latitude it receives maximum sunlight all over the year.
• Other regions on earth which are away from the equator receive tangential rays of the sun due earth's spherical shape.
• The polar regions of the earth near **Artic and the Antarctic circle receive the least sunlight.**​

Additional Information

• The Tropic of Capricorn lies at 23d 26' 22" latitude to the south of the Equator.
• The tropic of Cancer lies at 23d 26' 22" latitude to the north of the Equator.
• The area between The tropic of Capricorn and Cancer is called Torrid Zone.
• Poles are places on Earth's surface on which Earth's imaginary spin axis passes through.

The correct answer is Paris (France).

Key Points 

• UNESCO’s Headquarters are located in Paris, France.
• United Nations Educational, Scientific and Cultural Organization (UNESCO) is a specialized agency of the United Nations (UN).
• It seeks to build peace through international cooperation in Education, the Sciences, and Culture.
• It has 193 Members and 11 Associate Members (As of April 2020).
• Three UNESCO member states are not UN members: Cook Islands, Niue, and Palestine.
• UNESCO was founded on 16 November 1945.
• The first session of the General Conference of UNESCO was held in Paris in November-December of 1946.

Additional Information 

• Few important bodies and their headquarters:

The correct answer is Y C Deveshwar.

Key Points

• YC Deveshwar, ITC’s longest-serving corporate chief.
• He passed away at a private hospital in May 2019.
• He stepped down from the executive role in 2017 but remained as a chairman in a non-executive capacity.
• Sanjiv Puri is the current CEO and MD of the company. (As of August 2022)

The correct answer is France.

Key Points 

• International Criminal Police Organization (Interpol)
• It is an international organization that facilitates worldwide police cooperation and crime control.
• Headquarters: Lyon, France.
• President: Ahmed Naser Al-Raisi
• It is formed in 1923 as the International Criminal Police Commission and started calling INTERPOL in 1956.
• India joined the organization in 1949.
• INTERPOL enables police in their 194 member countries to work together to fight international crime.

Additional Information 

The National Literacy Mission (NLM) is a nationwide program started by Government of India in 5th May 1988 with an aim to eradicate illiteracy in the country by imparting functional literacy to non - literates.

Key Points

• The National Literacy Mission Authority (NLMA) was established specifically to address adult literacy in India.
• Its primary objective was to eradicate illiteracy by imparting functional literacy to non-literates, particularly focusing on disadvantaged groups like women, scheduled castes and tribes, and backward classes.
• The operations of the Mission were extended in 1999, with emphasis on lifelong learning and decentralization, with devolution of authority to the state and the district level institutions.

Therefore, it can be concluded that the main purpose of NLMA is to impart a new sense of urgency and seriousness to adult education.

National Curriculum Framework (NCF), 2005 provides a guideline with which teachers and schools can choose and plan experiences that they think children should have.

• It seeks to reform the curriculum and to bring learning experiences in and outside the classroom.
• It should be noted that the inquiry-based approach is suggested for teaching science in schools.

Important Points

An inquiry-based approach emphasizes to connect the child with their own experiences by posing questions and making decisions in the search of new understanding.

The following are the skills required in inquiry and decision-making:

• Skill in recognizing a problem
• Skill in developing hypotheses
• Skill in exploring
• Skill in validating hypotheses
• Skill in drawing conclusion

Hence, we conclude that the above statement is about inquiry approach.

Educating children with special needs who may not benefit from regular school education calls for changes in curricula, classroom arrangements, provision of aids and appliances, additional finances, and appropriate teacher preparation. The preparation of special teachers in India has many problems which need to be addressed.

Key PointsVarious training programs are organized to train teachers for special education. Periodic short-term programs varying from 2 weeks to 3 months, based on the need, should be made mandatory for all trained professionals.

• In-service training programs of one to two weeks' duration for general educators and special educators in all the disabilities and in specific areas of disability, are essential to effectively teach children with disabilities.
• Pre-service programs at degree and post-graduate levels are necessary to improve the quality of teacher training and to promote research and development activities in the field of special education.
• All universities should have a department of special education to promote the education of children with disabilities. Periodic evaluation of the training programs and constant updating to meet the challenges of changing trends in special education should be part of the planning of teacher preparation.

From the above points, we can conclude that 1 - 2 weeks of minimum training is required for teachers when children with ‘mild to moderate’ disabilities are included in their classrooms.

Piaget’s stage theory describes the cognitive development in children. Cognitive development involves changes in cognitive processes and abilities. In Piaget’s view, early cognitive development involves processes based upon actions and later progresses into changes in mental operations.

Key Points

Jean Piaget has given various stages for each type of activity, the two stages which are responsible for the mental representation and functioning are the later sensorimotor stage and early pre-operational stage.

Stage I: Sensory-motor stage:

• This stage lasts from birth to about two years old. The infant uses his or her senses and motor abilities to understand the world, beginning with reflexes and ending with complex combinations of sensorimotor skills. Children begin to develop symbols to represent events or objects in the world in the final sensory motor sub-stage.

Stage II- Preoperational stage:

• The preoperational stage lasts from about two to about seven years old. Now that the child has mental representations and is able to pretend, it is a short step to the use of symbols. Language development is one of the hallmarks of this period.

From the above points, we can conclude that children become capable of engaging in activities that involve mental representation, such as pretending, by the end of the pre-operational period.

Additional Information

• Concrete Operational Stage: The concrete operational stage starts from seven years of age and continues till 11 years. Children develop logical thinking but they still find difficulty in applying logic to hypothetical situations.
• Formal Operational Stage: The formal operational stage begins around 11 years of age and continues till 15 years. Here, children are able to perform higher-order mental operations. Their thought is flexible and they can deal effectively with complex problems involving reasoning.

Key Points 

Right to Education Act

The Act is completely titled “the Right of Children to Free and Compulsory Education Act”. It was passed by the Parliament in August 2009. When the Act came into force in 2010, India became one among 135 countries where education is a fundamental right of every child.

The 86th Constitutional Amendment (2002) inserted Article 21A in the Indian Constitution which states:

• “The State shall provide free and compulsory education to all children of 6 to 14 years in such manner as the State, may by law determine.”
• As per this, the right to education was made a fundamental right and removed from the list of Directive Principles of State Policy.
• The RTE is the consequential legislation envisaged under the 86th Amendment.

This act emphasizes learning by doing, curricular and co-curricular activities, and continuous and comprehensive evaluation.

Important Points

• According to the Right of Children to Free and Compulsory Education (RTE) Act 2009, the teacher in present-day classrooms should design activities/learning tasks that will both, engage and challenge.
• When a student engages in any activity he feels excited, creates interest in it, and feels motivated.
• Activity should be challenging that will develop good skills in a student.

The Act prohibits:

• Mental harassment and physical punishment.
• Screening procedures for the admission of children.
• Capitation fees.
• Private tuition by the teachers.
• Running schools with no recognition.

Hence, we can conclude that the teacher in present-day classrooms should design activities/learning tasks that will both, engage and challenge.

Most people are familiar with only the computational aspects of mathematics and so are likely to argue for its place in the school curriculum and for traditional methods of instructing children in computation. In contrast, mathematicians see computation as merely a tool in the real stuff of mathematics, which includes problem-solving, and characterizing and understanding structure and patterns.

• Teachers’ ideas about mathematics, mathematics teaching, and mathematics learning directly influence their notions about what to teach and how to teach it—an interdependence of beliefs and knowledge about pedagogy and subject matter.
• Here, we examine if a teacher instructs the students in his class to construct paper planes. This is an example of integrating mathematics in crafts. As, mathematics instruction that are viewed as being close to the current vision of exemplary instruction. In this way, this activity is facilitating the concept of geometry to the learners.

​Hence, it can be concluded that if a teacher instructs the students in his class to construct paper planes, it is an example of integrating mathematics in crafts.

Rabindranath Tagore, recipient of the Nobel Prize for Literature in 1913, is internationally known as a great poet. He was born in the year 1861, in Calcutta, Bengal. From his earliest days, Rabindranath grew up in a house where all the changes emerging in Indian society of that time were being felt in his day-to-day life. In Bengal, this change more often known as Renaissance, found expression in three great movements, religious, literary and national and all these three movements found their votaries in the Tagore family. In an atmosphere like this Tagore himself started writing poems at the age of eight and at the age of thirteen his poems were published in a Bengali monthly magazine, Bharati, under the name of Bhanusimh. Tagore's Philosophy of Education:

• Tagore laid great stress and emphasis on the aesthetic development of the senses in his philosophy of education.
• He argued that the development of the senses was as important as intellectual development.
• He, therefore, gave prominence to music, literature, art, dance, and drama in the daily life of the school. Hence, he quoted "Literature, music, and arts, all are necessary for the development and flowering of a student to form an integrated total personality."
• Tagore believed in an all-round development of personality and in his institution education continues to address the all-round development of the students.
• Education can develop a new pattern of life which culminates in the realisation of Universal man.
• Tagore's system of education emphasises the intellectual, physical, social, moral economic and spiritual aspects of human life by which a man can develop an integrated personality.
• Tagore believed that along with education, economic upliftment is also necessary.
• Since economic life covers the whole width of the fundamental basis of society because its necessities are the simplest and the most universal, he suggested that educational institutions, in order to obtain their fullness of truth, must have close associations with this economic life. “Our university must not only instruct, but live; not only think, but produce".

Hence, we conclude that the above statement is given by Tagore.

Education occurs in many forms for many purposes through many institutions since the emergence of society. There are three forms of education - formal, non-formal, and informal.

• Informal education can be acquired or imparted anywhere, anytime, and by anyone. Non-formal education is imparted in a semi-rigid environment and can be acquired by anyone.

Key Points

• India has had a rich tradition of learning and education from the beginning of civilization. Education policy in ancient India in its traditional form was closely related to religion.
• Over a period of time, two systems of education have developed- the Vedic, which is further subdivided into post-Vedic and/ or Brahminic, and the Buddhist.
• During the Vedic period, India had a Gurukul system of education in which anyone who wished to study went to a teacher’s (Guru) house (Ashram) and requested to be taught.
• If accepted as a student (disciple) by the Guru, s/he would then stay at his place and help in all activities at home.
• This system not only created a strong tie between the teacher and the taught (like family members), but also taught the learner everything about running a house.
• The Guru taught everything the child wanted to learn, from Sanskrit to the Holy Scriptures and from Mathematics to Metaphysics.
• The student stayed as long as s/he wished or until the guru felt he had taught everything he could teach. All learning was closely linked to nature and life and not confined to memorizing information

From the above points, we can conclude that the formal nature of imparting education started during the Vedic Period through the gurukuls, ashrams, and parishads.

Additional Information

• Mughal Period:  Muslim rulers promoted urban education by establishing libraries and literary societies. They founded primary schools (maktabs) in which students learned reading, writing, and basic Islamic prayers and Secondary Schools (madrasas) to teach advanced language skills (mainly Arabic and Persian) in India.
• Buddhist Period:  Buddhist education was also imparted in Mathas. Entry to higher education was very selective and competitive and only the best managed to enter the citadel of higher learning.

The role of a teacher while implementing the constructivist method of teaching in mathematics is to ensure that students are involved in gleaning knowledge on their own.

Key Points

• Constructivist Methods of teaching mathematics aim at connecting mathematics to daily life instead of just cramming the formulas.
• It allows students to use creative methods to understand mathematics and solve it in a creative manner.

Additional Information

• Teachers can follow various constructivist approaches, like, reciprocal learning, inquiry-based learning, cooperative learning, problem-solving learning.
• Reciprocal learning allows the grouping of children and allows interaction and exchange of knowledge.
• In an Inquiry-based learning method, learners frame their own questions and try to answer them.

Hence, we can conclude that to ensure that students are involved in gleaning knowledge on their own is the role of a teacher while implementing constructivist method of teaching in mathematics.

The draft of the National Education Policy (NEP) 2020 was released by the MHRD.

• The focus of the policy is to address gender discrimination, the creation of educational tribunals, and a common curriculum for Science, Mathematics and English.
• The motto of the new policy is “Educate, Encourage, Enlighten”.
• The reason for lowered credibility of the higher education system is the lack of academic monitoring to ensure good quality of education in the classrooms. So, its vision is to create a credible education system capable of ensuring inclusive quality education and lifelong learning opportunities for all.
• Among others, the mission includes: Ensuring an equitable, inclusive and quality education for all; fostering quality education with a strong focus on education reforms; promoting acquisition by all learners of relevant skills, including technical and vocational skills, for work and entrepreneurship.

​Hence, the reason for lowered credibility of the higher education system is the lack of academic monitoring to ensure good quality of education in the classrooms.

Teachers play the most crucial role in the life of a child, especially in the understanding of complex concepts in children through planning and dedication.

Cognitive powers of a child, like imagination power, intelligence, ability to make a decision, etc. are related to the child's 'mental development' as mental development:

• refers to the development of the ability to understand, learn, reason, think, perceive, and solve a problem.
• refers to the development of the ability to explore and process information to learn and understand the things around him.
• includes the acquisition of those abilities which help the individual to make sense i.e. perceiving, organizing, storing, retrieving, utilizing, and transacting.

Note that:

• Children should be asked creative questions to promote their imagination and make their understanding better.
• Insisting on the same answers from all children will hinder the growth of the child’s own understanding and imagination.

 Important Points

• Science is a very practical subject that has direct relevance to our lives.
• To understand the practical relevance of the subject, learners must be able to make connections between the science they learn at school and their everyday lives.
• It will keep the students motivated and interested in learning.
• Doing practical work and encouraging students for activities is an important step to motivate students.
• To become a resourceful educator one can –
• Make maximum use of the local environment as a teaching aid. It can be then carried for investigations, discussions, and sources of classroom data.
• Make maximum use of the local community as a teaching aid. For example, students can reach out to parents for helping them locate stories, opinions on everyday issues or just observe their parents on how they interact with the environment.
• Make maximum use of communication systems like radio, television, etc.
• Connect with other schools and get inspired by each other’s initiatives.

Key Points

• A home assignment where the learners make full use of local materials is an interesting and important method to make learners understand the environment around them.
• Among all the activities stated, identifying the parents as a teaching aid and a local resource is done when the learners are asked to observe the materials that their mothers discard and finding out their possible harmful effects if eaten.

Hence we can conclude that out of the given activities, the activity which will require the students to use local material would be -  observing the materials that their mothers discard while cleaning rice/wheat by handpicking. Identify the impurities and try to find out their possible harmful effects if eaten. 

Confusion Points 

• ​Although gathering information about countries facing a shortage of food, its causes and effects through newspapers, magazines, and the internet, is an example of encouraging learners to move beyond the textbooks but it is not making use of locally available resources and making a contextual understanding.

Piaget’s theory of cognitive development is a comprehensive theory about the nature and development of human intelligence first developed by Jean Piaget.

• It is primarily known as a developmental stage theory, but in fact, it deals with the nature of knowledge itself and how humans come gradually to acquire it, construct it, and use it.

Key Points

• According to Piaget, the basis of learning in a child’s early years is drama. Creative drama is particularly an enabling experience that sharpens children's gaze and observation.
• Drama can be introduced as a classroom resource in many different ways, such as having a doll's house where children get familiar sets to explore and the opportunity to pretend to be the people with whom they live.
• Children can also have access to baskets of pops (such as sandals and shoes, old pairs of spectacles, purses, bags, and dupattas) to play with and impersonate adults inhabiting their environments for the sheer joy of being 'the other'. Such opportunities lead to acts that foster curiosity, confidence, and conviviality.

Hence, it is clear that the basis of learning in a child’s early years is drama, as per the research and philosophy of Jean Piaget.

Patriarchy is a system of society or government in which the father or the eldest male is the head of the family and descent is reckoned through the male line.

Key Points

• Patriarchy is the term used to describe the society in which we live today, characterized by current and historic unequal power relations between women and men whereby women are systematically disadvantaged and oppressed.
• This takes place across almost every sphere of life in the form of under-representation in the workforce, in decision-making positions, and in government institutions. Male violence against women is also a key feature of patriarchy.
• In the patriarchal view of society, elders and other family members are not available to care for the child in the absence of the mother. Sometimes, she has to leave their young, growing children in the care of older siblings.
• The patriarchal view of society focuses on women being subject to oppression. Women are primarily housewives and mothers, and only an insignificant few are in the workforce.

From the above points, we can conclude that 'in poorer classes, older people continue to work for as long as they can' is the correct answer as it is not related to the patriarchal view of society.

Important PointsChild-centered pedagogy: Child or student-centered pedagogy can be broadly applied to many levels of education. Teachers who champion this approach are those who wish to promote in their students a love of learning, provide a safe and caring environment, and work towards perfecting their craft in an active way. In this approach, we connect school knowledge to outside knowledge.

• The constructivist approach relies on continuous evaluation and growth monitoring to help students think about themselves as agents of their own learning.
• Children sharing and integrating school knowledge with their experiences in and out of the school. This makes learning easy and natural.
• Developing a tendency for the all-around development of the child.
• Develop learning by doing.
• In child-centered education, curriculum, teaching method, classroom environment, evaluation, teaching material, activities will be made keeping in mind all the students.

Additional Information Children working in groups and pairs for learning a topic and Children sharing their experiences in the classroom with peers and the teacher is an example of progressive education.

• Progressive education: Progressive education is a pedagogical movement that began in the late nineteenth century and has persisted in various forms to the present. The Father of Progressive education is John Dewey. 
• Group work and development of social skills
• Collaborative and cooperative learning projects
• De-emphasis on textbooks in favor of varied learning resources
• Emphasis on learning by doing – hands-on projects, expeditionary learning, experiential learning.

Hence, we can conclude the right answer to this question is children sharing and integrating school knowledge with their experiences in and out of the school.

Concept:

• pH (Power of Hydrogen): The degree of acidity or alkalinity of a substance is expressed in pH value.
• pH is a scale (0 to 14) used to specify the acidity or basicity of an aqueous solution.
• Lower pH values of solutions represent more acidic in nature,
• While higher pH values of solutions represent more basic or alkaline.

 

pH = - log [H⁺] For acid

pOH = - log [OH^-] For base

${\rm{pH}} = {\rm{pKa}} + \log \left[ {\frac{{{\rm{salt}}}}{{{\rm{acid}}}}} \right] = {\rm{pKa}}$ For buffer solution

Buffer solution: A buffer solution contains either a weak acid and its salt with a strong base or a weak base and its salt with strong acid.

Calculation:

Let us assume in the original mixture,

[salt] = [acid]

${\rm{pH}} = {\rm{pKa}} + \log \left[ {\frac{{{\rm{salt}}}}{{{\rm{acid}}}}} \right] = {\rm{pKa}}$ For buffer solution

Now, the ratio of the concentration of acid to salt is increased tenfold.

$\frac{{\left[ {{\rm{Acid}}} \right]}}{{\left[ {{\rm{Salt}}} \right]}} = \frac{{10}}{1}$

So, $\frac{{\left[ {{\rm{Salt}}} \right]}}{{\left[ {{\rm{Acid}}} \right]}} = \frac{1}{{10}}$

${\rm{pH}} = {\rm{pKa}} + \log \left[ {\frac{1}{{10}}} \right] = {\rm{pKa}} - 1$

Thus pH of the solution decreases by 1.

Important Points

• The scale runs from 0 to 14, with acids having a pH less than 7, 7 being neutral, and bases having a pH higher than 7.
• Acids and bases react with each other in what is called a neutralization reaction.

 

Explanation:

• Allotropy: The presence of one element in various structures, having distinctive physical properties, however, comparable chemical properties are known as Allotropy.
• Diverse types of an element are called “allotropes" or Allotropic Structures.
• Carbon, sulfur, phosphorous, etc. demonstrates allotropy.

Carbon has different types of allotropes diamond, graphite, fullerene, etc.

• Diamond:
• It is a well-known allotrope of carbon.
• It exhibits high hardness, high melting point, thermal conductivity, and high dispersion of light.
• It is the hardest known natural mineral.
• It is widely used in cutting, jewellery, and as a potential semiconductor material.
• Graphene:
• It is also an allotrope of carbon
• It is a sheet of a single layer of carbon atoms
• Layers of graphene make up graphite.
• The strong covalent bonds between the carbon atoms of graphene.
• Graphite is soft because it has weak intermolecular forces between its layers.
• It is widely used in electronics.
• Fullerene:
• It is also an allotrope of carbon.
• Fullerenes are used in several biomedical applications like carriers of genes etc.

Concept:

• The type of collision in which the total kinetic energy of the system remains constant before and after the collision is called elastic collision or perfectly elastic collision.
• As there is no net external force on the system, so momentum before the collision and after the collision will remain the same.

 

Linear Momentum before the collision (P₁) = Linear Momentum after the collision (P₂)

P₁ = m₁u₁ + m₂u₂

P₂ = m₁v₁ + m₂v₂

m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂

 

Explanation:

Given that: u_A = 30 cm/s = 0.3 m/s towards west, u_B = 40 cm/s = 0.4 m/s towards north, mass of A & B = 1000 kg.

From the figure, we can find the resultant velocity of A & B,

${\rm{R}} = \sqrt {{{0.3}^2} + {{0.4}^2}} = \sqrt {0.25} = 0.5$

R = 0.5 m/s

Total system momentum = net mass × net velocity

= 1000 × 0.5

Total system momentum = 500 kg m/s, NW.

The correct answer is Decomposition rate would decrease and NEP would increase.

Concept:

• Decomposition:
• Breakdown of the organic material to recycle it back into the environment.
• Net ecosystem production:
• The total accumulation of new biomass minus the costs of respiration by all of the organisms of the ecosystem.
• Fungicide:
• Fungi are decomposers, while fungicide is used to kill the fungus.

Explanation:

• As we apply the fungicide to the cornfield the decomposers as fungi die.
• So the rate of decomposition decreases.
• If no decomposition takes place so no biomass is disappearing.
• And only new biomass is adding that will increase the NEP.

Notes:

• Some names of compounds:
• Insecticides – insects
• Herbicides – plants
• Rodenticides – rodents (rats & mice)
• Bactericides – bacteria
• Fungicides – fungi
• Larvicides – larvae

The correct answer is Nasal.

Key Points

• The bones of the skull and three thin membranes called meninges are there to protect the brain.
• The brain is also cushioned and protected by cerebrospinal fluid.
• The skull is made up of 29 bones.
• The only bone that can move is Mandible.
• The nasal bone is part of the Skullbone.

​

• The atlas bone is the first of seven cervical vertebrae that supports the weight of the skull.
• The tibia is the bone that forms the shin part of the leg.
• The femur bone is the largest bone of the body, it is the thigh bone.

Notes:

• Some important names of bones:
• Knee- Patella
• Thigh- Femur (largest bone)
• Ankle- Tarsal
• Fingers- Phalanges
• Wrist- Carpals
• Upper arms- Humerus
• Palm- Metacarpal
• Bones in ear- Malleus, Incus, Stapes (smallest bone)

The correct answer is pickling.

Explanation:

 

So the phenomenon of removing layers of basic oxides from metals before electroplating is called pickling.

Concept:

• Doppler Effect: If the source or the observer or both, move with respect to the medium, the frequency observed may be different from the frequency of the source. This apparent change in frequency of the wave due to the motion of the source or the observer is called the Doppler Effect.
• Reflection: The phenomena in which light ray is sent back into the same medium from which it is coming, on interaction with boundary, is called reflection.
• Refraction: When a ray of light passes from one medium to another it suffers a change in direction at the boundary of two media is called refraction.
• Diffraction of sound: Diffraction is the bending of a sound wave as it moves past an obstacle or through a narrow opening.
• i.e., if we have greater the wavelength, more distinct is the diffraction effect. It is due to this reason that the diffraction effect is very commonly observed in sound.

 

Explanation:

• By the diffraction of sound transform acoustical energy into acoustical shadows.
• These are areas that are prevented from the direct incidence of sound as by an obstacle.
• Due to diffraction possible to hear the noise of a road even in the backyard of a building, or the sound of the referee's whistle when standing behind him.

Concept:

Geomagnetic Strom: When solar matter (solar winds) collides with the planet at high speed, then the surrounding magnetic field of the planet deflected towards their pole.

• This disturbance in the atmosphere of the planet with the burst of radiation and charged particles termed as a geomagnetic storm.

 

Microwaves:

• It is an electromagnetic wave that comes in the range of 1 mm to 1 meter and of the frequency range between 300 MHz to 300 GHz.
• Microwaves are generally used in Radars, Transmission towers, Microwave Ovens, etc.
• These waves are micro not in terms of wavelength but micro from radio waves with greater frequency.
• Microwave links are used space wave propagation mode of transmission i.e. LOS (line of sight)

 

Explanation:

The solar winds created by the charged particles coming out from the sun that causes the geomagnetic storm on earth.

The effects of the geomagnetic storm are:-

• It fluctuates the magnetic field of the earth.
• The aurora seen at poles are because of geomagnetic storms.
• Sometimes, it disrupts the electrical power transmission lines.

 

Microwave, on the other hand, do not much affected by it because it is an electromagnetic wave and it is used in LOS (line of sight) propagation transmission.

Hence, the correct option here is microwave propagation.

Concept:

This is an anatomical detailed diagram of a human eye.

• In this Eye lens is a transparent, biconvex structure in the eye which provides finer adjustment required to focus objects on the retina
• And iris is a Dark muscular diaphragm between the cornea and the lens controls the size of the pupil
• The retina is the light-sensitive surface of an eye on which the image is formed it generates signals which are transmitted to the brain through optical nerves
• Hence eye lens is just like an ordinary bifocal convex lens which will act as a converging lens and

 

Explanation:

The anterior part (front part) of the eye is having a transparent liquid called Aqueous humour. It helps to maintain the shape of the eye.

• Also, the aqueous humour helps to bend maximum light towards the pupil.
• Thus, the correct option is Aqueous Humour.

Concept:

• Molarity (M) is defined as the number of moles of solute (n) divided by the volume (V) of the solution in litres.

 

$Molarity;\left( M \right) = \frac{{No.;of;moles;of;solute;\left( n \right)}}{{Volume;of;the;solution;\left( V \right)}}$

Explanation:

We know that,

Volume is directly proportional to Temperature i.e. V ∝ T

So, if the temperature increases means the volume also increases.

Also,

$Molarity;\left( M \right) = \frac{{No.;of;moles;of;solute;\left( n \right)}}{{Volume;of;the;solution;\left( V \right)}}$

$\Rightarrow M \propto \frac{1}{V}$

Hence, if volume increases then Molarity (M) decreases.

⇒ If Temperature increases molarity (M) decreases.

The correct answer is RNA virus.

Concept:

• The term Virus in Latin means Poison.
• Viruses are small submicroscopic pathogenic agents that infect all the different life forms, from animals and plants to microbes and archaea.
• TMV was the first discovered virus.
• The study of Virus is called Virology
• The virus can be divided into two types based on the genetic material present
• DNA virus:
• It is a virus that has DNA as its genetic material.
• It replicates using DNA.
• RNA virus:
• It is a virus that has RNA as its genetic material.
• It replicates using RNA.

Explanation:

• Tobacco mosaic is an example of an RNA virus.
• Here is the list of DNA and RNA virus:

Additional Information 

• RNA - 
• ​Ribonucleic acid.
• RNA contains four different bases: Adenine, Guanine,  Uracil, and Cytosine.
• DNA - 
• Deoxyribonucleic acid
• It contains four different bases: Adenine (A), Guanine, Cytosine, and Thymine (T).
• DNA and RNA were discovered in 1869 by Swiss researcher Friedrich Miescher.
• Virology is the study of viruses.
• HIV - Human immunodeficiency virus
• AIDS - Acquired immune deficiency syndrome

The correct answer is  9.22 mol/m3.

• Particle density:
• It is defined as the number of moles per unit volume(in m³).
• SI unit is mol/m³.
• Formula used
• Particle density =  (No. of moles x 10⁶) / volume(in cm3)
• No. of moles = Total no. of atoms / 6.022 x 10²³
• Calculations:

Total number of atoms in cubic centimeter =  5.55 × 1018

No of moles = 5.55 × 1018 / 6.022 x 1023

​                    = 0.9216 x 10^-5

Now Particle density  = 0.9216 x 10^-5 x 10⁶ 

    Particle density  = 9.22 mol/m3

Concept:

• Cytochalasin B is a cell-permeable mycotoxin, it shortens actin filaments by blocking monomer addition at the fast-growing end of polymers.

Explanation:

• The drug cytochalasin B blocks the function of actin by disrupting the cleavage furrow formation and cytokinesis.
• Cytochalasin B works by inhibits the actin filament polymerization through binding to the fast-growing end of F actin filament thereby inhibits the cleave furrow formation and cytokinesis

Additional Information

• The cytokinesis is the process of division of cytoplasm. In animals, cell cytokinesis is achieved by means of a constricting belt of actin filaments. During telophase, the last stage in mitosis, a contractile ring forms on the cytoplasmic membrane surface at the cleavage furrow. This contractile ring contracts, forming a cleft between two cells that are separating. Just before telophase, actin filaments begin to form at the site that will become the cleavage furrow.
• Actin filaments (F-actin) are linear polymers of globular actin (G-actin) subunits and occur as microfilaments in the cytoskeleton and as thin filaments, which are part of the contractile apparatus.

Concept:

Aromatic compound:

• Hydrocarbons containing sigma bonds and delocalized pi electrons between carbon atoms in a ring.
• For example, benzene. They are known as aromatic due to their pleasant smell.

Properties of Aromatic compound:

• The aromatic compound must be Cyclic.
• The aromatic compound produces the sooty yellow flame on the burning due presence of high density of hydrogen and carbon present in the compound.
• the aromatic compound must have (4n + 2) pi Electrons (n = 1,2,3,4,...)
• The aromatic compound doesn't prefer the  Addition reaction but Prefer Substitution substitution
• The compound must Possess Resonance Energy

Explanation:

Coal tar:

• It is obtained by cooling the gas that is formed during the destructive distillation of coal to approximately ambient temperature.
• It is a black, viscous liquid composed primarily of a complex mixture of condensed-ring aromatic hydrocarbons.
• Coal tar is an aromatic compound with stable carbon rings.

Hence, Coal tar is the main source of aromatic compounds.

Additional InformationAliphatic compounds​ - 

• The Aliphatic compound is the chemical compound belonging to carbon in which the atoms are connected by single, double, or triple bonds to form nonaromatic structures.

Heterocyclic compounds-

• These are cyclic compounds with the ring containing carbon and another element, the component being oxygen, nitrogen and sulfur.
• The simplest of the five-membered heterocyclic compounds are pyrrole, furan and thiophene, each of which contains single heteroatoms

Cycloalkanes

• These are alkanes joined in a closed loop to form a ring-shaped molecule, they are named by using the alkane names above, with cyclo-as a prefix.
• These start with propane, or rather cyclopropane, which has the minimum number of carbon atoms to form a closed shape: three atoms, forming a triangle

CONCEPT:​

• Resolution of vectors into components: We have a vector (F) where the magnitude of the vector is F and the angle with horizontal is θ.

 

The vector has two components:

1. Vertical component
2. Horizontal component

 

Vertical component (F_y) = F Sinθ

Horizontal component (F_x) = F Cosθ 

$F = \sqrt {F_x^2 + F_x^2}$

Explanation:

Here, the component of Y makes the ball to fly high or remain most of the time in the sky

Vertical component is the function of sin θ

Other than 90° all the angles give less height to the ball.

⇒ for maximum height, θ must be 90°

Hence, at 90° the ball will have the highest time in the atmosphere.

The correct answer is Formation of prothrombin.

Concept:

• Blood coagulation Process:
• It is the process of clot blood using platelets and fibrin in the blood.
• It is required to reduce the loss of blood from the body.
• This process is called Hemostasis.
• Some steps are there in this process:
• The primary step is vasoconstriction, in this vascular wall react to reduce the loss of blood.
• Then platelets start covering the injured area.
• It activates fibrin clot know as secondary hemostasis.
• It follows the formation of fibrinogen, which is a soluble plasma protein.
• Platelet clots are termed as a white thrombus and if the red blood cells are present, it is known as red thrombus.

Explanation:

• There are different processes in the coagulation process.
• Formation of Thromboplastin, thrombin, fibrin from prothromboplastin, prothrombin, and fibrogen respectively.
• Prothrombin is not formed as part of the blood coagulation process; rather, it is a precursor to thrombin and is present in the blood plasma.

Notes:

• There is a series of steps leading to the formation of fibrin protein fibre, it involves different clotting factors.
• There are about thirteen known clotting factors:
• Fibrinogen (Factor 1)
• Prothrombin (Factor 2)
• Thromboplastin (Factor 3)
• Calcium (Factor 4)
• Proaccelerin or Labile Factor (Factor 5)
• Stable Factor (Factor 6)
• Antihemophilic Factor (Factor 8)
• Christmas Factor (Factor 9)
• Stuart - Power Factor (Factor 10)
• Plasma Thrombin antecedent (Factor 11)
• Hegman Factor (Factor 12)
• Fibrin Stabilising Factor (Factor 13)

The correct answer is 206.

Explanation:

The body's internal structure is the Human skeleton.

• This is made up of 300 bones at birth-this number falls by adulthood to 206 bones as certain bones have fused. In the skeleton, the bone mass reaches maximum density around age 30.
• Bones are connected to other bones by long fibrous straps called ligaments.
• Tendons connect muscle to bone.
• Ligaments and Tendons both are made of collagen.
• Many factors work together to ensure the strength and health of bones. Bone density relies on:
• A steady supply of dietary calcium
• Adequate vitamin D from sunshine and food
• A healthy diet with plenty of vitamins and minerals
• Various hormones including parathyroid hormone, growth hormone, calcitonin, oestrogen, and testosterone
• Regular weight-bearing exercise.

Additional Information

The human skeleton is made up of 206 bones, including bones of the:

• The femur (the thigh bone) is the largest bone in the human body whereas the stapes (bone of ear) is the smallest bone of the body.
• Skull: including the jaw bone
• Spine: cervical, thoracic and lumbar vertebrae, sacrum, and tailbone (coccyx)
• Chest: ribs and breastbone (sternum)
• Arms: the shoulder blade (scapula), collar bone (clavicle), humerus, radius, and ulna
• Hands: wrist bones (carpals), metacarpals, and phalanges
• Pelvis: hip bones
• Legs: the thigh bone (femur), the kneecap (patella), shin bone (tibia) and fibula
• Feet: tarsals, metatarsals, and phalanges.

The correct answer is 5.0.

Concept:

• Neutralization: It is a chemical reaction in which an acid and base quantitatively react together to form a salt and water as products.
• acid + base → salt + water

Formula used:

• M₁ x V₁ x (equivalents) = M₂ x V₂ x (equivalents)

Given 

• Reaction:
• H₂SO₄ + 2NaOH → Na₂SO₄+ 2H₂O
• V1 = 10 ml
• M1 = 1 M
• equivalents of NaOH = 1
• V2 =?
• M2 = 1M
• equivalents of H₂SO₄ = 2

Calculations:

• M1 x V1 x (equivalents) = M**₂** x V₂ x (equivalents)
• 1x10x1 = 1xV₂x2
• V₂ = 5 ml
• So volume of H₂SO₄ required to neutralise the NaOH is 5 ml.

The correct answer is Alec Jeffreys.

• DNA fingerprinting is a technique that shows the genetic makeup of living things.
• Father of DNA fingerprinting in the world is Sir Alec John Jeffreys.
• Father of DNA fingerprinting in India is Dr Lalji Singh.

Additional Information

Some other important names:

The correct answer is A – 3; B – 1; C – 4; D – 2; E - 5.

• Trait:
• It is a specific characteristic of any organism.
• It refers to any genetically determined characteristic of an organism.
• It is variant for a definite character.
• Genotype:
• It is the total sum of genes transferred to offspring by parents.
• It is a set of heritable genes which are transferred between generations.
• It is the unique genetic constitution of an organism or genetic makeup of an individual.
• Allele:
• It is an alternative version of a gene.
• Any organism inherits two alleles for each gene, one from each parent.
• If both the alleles are the same, the individual is homozygous.
• If both the alleles are different, the individual is heterozygous.
• Testcross:
• It is the breeding of specie with a recessive specie.
• It was introduced by Gregor Mendel.
• A cross between an individual with an unknown genotype and a homozygous recessive individual.
• Monohybrid cross:
• A cross between individuals heterozygous for a single character.
• It is a genetic mix between two individuals with homozygous genotypes which result in an opposite phenotype.

Notes:

• Dihybrid cross:
• It is a cross between two different genes that differ in their observed traits.
• It is a cross between two individuals that are heterozygous for two different traits.
• Difference between genotype and phenotype:

• Backcross:
• It is a hybrid cross with one of its parents, or an adult genetically identical to the parent, to achieve offspring with a genetic identity closer to the parents.
• It is used mainly in horticulture, animal breeding.

The correct answer is Gibb’s Helmholtz.

• Given ΔG = ΔH – TΔS equation is Gibbs Helmholtz equation.
• G = Gibbs free energy
• H = enthalpy
• T = temperature
• S = entropy
• ΔG>0; the reaction is non-spontaneous and endergonic
• ΔG<0; the reaction is spontaneous and exergonic
• ΔG=0; reaction is at equilibrium
• Maxwell equation:

Notes:

• Laws of Thermodynamics:
• There are four laws of thermodynamics:
• Zeroth law of thermodynamics
• If two thermodynamic systems are in thermal equilibrium with a third system then they separately are in thermal equilibrium with each other.
• First law of thermodynamics
• Energy can neither be created nor destroyed, but it can be changed from one form to another.
• Second law of thermodynamics
• The energy in the form of heat only flows from a higher temperature to that of lower temperature.
• Third law of thermodynamics
• The entropy of a system approaches a constant value as its temperature approaches absolute zero (i.e 0 K).

The correct answer is Secondary xylem.

• Xylem
• It is a type of vascular tissue which transports water and nutrients from roots to stem and leaves.
• And they also provide mechanical strength to the plants.
• They are of two types:
• Primary xylem:
• They originate from procambium that further divided into protoxylem and metaxylem.
• Secondary xylem:
• They originate from the vascular cambium.
• It is responsible for the increase in the girth of the plant.
• They arise, directly or indirectly, from the meristematic activity.
• Phloem:
• It is a living tissue in vascular plants.
• It conducts the soluble organic compounds downwards from the leaves that are synthesized during photosynthesis.
• They are constituents of phloem:
• Companion cells
• Sieve tubes
• Phloem fibres
• Phloem parenchyma.

Notes:

• Meristematic tissue:
• Apical Meristem
• It is present at the tips of the roots and shoots
• It helps in the increase of the height of the plants.​
• Intercalary Meristem
• It is present in the leaves and internodes at the intercalary position.
• It helps to increase the length of the internode.
• Lateral Meristem
• It is present in the stems and roots on the lateral side.
• It helps to increase the thickness of the plant.
• Two lateral meristems are Vascular cambium and cork cambium.

The correct answer is Glucose.

Concept:

• Reabsorption is the process that moves water and solutes out of the filtrate and back into your bloodstream.
• The first absorption is done when they are absorbed into the bloodstream from the digestive tract after a meal.
• The functional unit of the kidney is the Nephron.
• Each kidney contains about 1 million or so Nephrons.
• The Parts of the Nephron
• Glomerulus
• Bowman’s Capsule
• Proximal Tubule
• Loop of Henle
• Distal Tubule
• Collecting Duct

Explanation:

• The proximal tubule is the tube between the Bowman’s capsule and the loop of Henle.
• Reabsorption of important nutrients like water, glucose, and amino acids begins here.
• Glucose is completely reabsorbed in the Proximal convoluted tubule. Around 65% of salts are reabsorbed in PCT.
• Water and Salts are reabsorbed in distal convoluted tubules and collecting ducts with the help of hormones like vasopressin and aldosterone.

​

Note:

• Different excretory parts of different animals:
• Unicellular Animals / Ameoba – Diffusion through the surface of the body.
• Platyhelminthes/ Flatworms – Flame cells.
• Roundworms/Earthworms – Nephridia.
• Arthropods/ Cockroaches – Malpighian tubules.
• Crustaceans / Prawns – Antennal glands / Green Glands.
• Vertebrates – Kidney.

Additional Information

• Nitrogenous waste can be divided into three groups based on its toxicity.

The correct answer is 15 σ – and 3 π - bonds.

Concept:

• Sigma Bonds:
• All single bonds are sigma bonds.
• They are formed by head-on overlapping between s-s, s-p, p-p orbitals.
• Pi Bonds:
• The overlapping orbitals must be unhybridized.
• It is formed by the sidewise overlap of atomic orbitals.
• It is weaker than sigma bonds.
• Double bonds have pie bond and sigma bond.

Explanation:

• To calculate the sigma bonds, count the number of single bonds and double bonds.
• To calculate the pi bonds count the number of double bonds.
• So in Toulene - 15 sigma and 3 pi bonds.
• Naphthalene - 19 sigma and 5pi bonds.

The correct answer is basidiomycetes.

Concept:

• Fungi constitute a unique kingdom of heterotrophic organisms.
• Fungi show a great diversity in morphology and habitat.
• Fungi are cosmopolitan and occur in air, water, soil, animals, and plants.
• The study of fungi is Mycology.
• Fungi are categorized into 4  classes: Phycomyctes, Ascomycetes, Basidiomycetes & Deuteromyctes

Explanation:

• Mushrooms belong to the class basidiomycetes as they contain puffball type structure.
• Their scientific name is Agaricus
• They are terrestrial and lead a saprophytic and parasitic mode of life.

Additional Information 

• Phycomycetes
• ‘Phycomycetes’ include fungal species of Oomycetes, Chytridiomycetes, and Zygomycetes.
• They are considered as lower fungi.
• Ascomycetes
• Ascomycetes include a wide range of fungi such as yeasts, powdery mildews, cup fungi, morels.
• e.g Morchella, Peziza
• Basidiomycetes
• Basidiomycetes include puffballs, toadstools, bird’s nest fungi, bracket fungi, stinkhorns, rusts, and smuts.
• e.g Agaricus, Geaster
• Deuteromycetes
• The fungi belonging to this group lack sexual reproduction and are called imperfect fungi.
• e.g  Pycnidium - Phoma, Acervulus - Colletotrichum

The correct answer is Small organic molecules that make up a part of an enzyme cofactor.

• Vitamins are small organic molecules that make up a part of an enzyme cofactor.
• For the protein's biological activity, a non-protein chemical compound that is required are cofactors of enzymes.
• Vitamins are made up of carbon, hydrogen and oxygen.
• Vitamins are called micronutrients because they are needed in only very small quantities.
• Vitamins are of two types:
• Water-soluble vitamins - B, C
• Fat-soluble vitamins - A, D, E, K

Notes:

Concept:

• Elasticity: The property of a body to regain its original configuration (i.e., shape and size) when the deforming force is removed is called elasticity.
• Perfectly elastic body: A body, which regains its original configuration immediately and completely after the removal of the deforming force, is called a perfectly elastic body.

 

For elongation of wire this relation is used,

${\rm{\delta }} = \frac{{{\rm{FL}}}}{{{\rm{AE}}}}$

Where, δ = elongation in wire, F = applied force, L = length of wire, A = cross-sectional area, E = modulus of elasticity of wire.

Explanation:

From elongation in wire relation

${\rm{\delta }} = \frac{{{\rm{FL}}}}{{{\rm{AE}}}}$

Where, δ = elongation in wire, F = applied force, L = length of wire, A = cross-sectional area, E = modulus of elasticity of wire.

∴ For breaking a wire,

${\rm{F}} \propto \delta$

therefore the extent of stretching is directly proportional to the applied force.

Concept:

• A mast cell is a migrant cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that mast cells are responsible for allergic reactions and inflammation.

Explanation:

• When mast cells are activated by an allergen that binds to serum IgE attached to their FcɛRI receptors, they release cytokines, histamine, heparin and growth factors and causes allergic reactions and inflammation.
• An allergy is an exaggerated reaction by the immune system in response to exposure to certain foreign substances.
• Inflammation is the response of the immune system to the affected tissue by recruiting many cells to kill the disease-causing microbes, it causes redness, warmth, swelling.
• Blast Cells refer to myeloblasts or myeloid blasts. These are the very earliest and most immature cells of the myeloid cell line.
• Stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and that have the capacity to self-renew and to generate multiple mature cell types.

So,  Mast cells are responsible for allergic reactions and inflammation.

Additional Information

• Mast cells were discovered by Paul Ehrlich.
• Mast cells derive from the bone marrow and are released into the blood as mast cell progenitors and do not fully mature until they are recruited into the tissue where they undergo their terminal differentiation.

Important cells of the Immune System

Concept:

• pH (Power of Hydrogen): The degree of acidity or alkalinity of a substance is expressed in pH value.
• pH is a scale (0 to 14) used to specify the acidity or basicity of an aqueous solution.
• Lower pH values of solutions represent more acidic in nature,
• While higher pH values of solutions represent more basic or alkaline.

<br>

pH = - log [H⁺] For acid

pOH = - log [OH^-] For base

• For buffer solution,

${\rm{pH}} = {\rm{pKa}} + \log \left[ {\frac{{{\rm{salt}}}}{{{\rm{acid}}}}} \right] = {\rm{pKa}}$

• Buffer solution: A buffer solution contains either a weak acid and its salt with a strong base or a weak base and its salt with strong acid. Buffers resist a change in pH when acids or bases are added to it.
• Buffer can be classified into two types;
• Acidic Buffer: The buffer is formed from the solution of a weak acid and its salt of a strong base. acid. Acidic buffers generally have pH less than 7. Example of acidic buffer is CH₃COOH and CH₃COONa.
• Basic Buffer: The buffer which is formed from the solution of a weak base and its salt with a strong acid. basic buffers have pH more than 7. Example of basic buffer is NH₄OH and NH₄Cl.

Explanation:

• CH₃COOH and CH₃COO^-, HCOOH, HCOO^- are all examples of an acidic buffer prepared by a combination of a weak acid and its conjugate base.
• ${\rm{H}}_2{{\rm{C}}_2}{\rm{O}}_4^ + {{\rm{C}}_2}{\rm{O}}_4^{2 - }$ an acid buffer formed by oxalic acid and its conjugate base oxalate. Hence, this is also an acidic buffer.
• H₃BO₃ and BO₃^- is an acid buffer formed by boric acid and its conjugate base borate. Hence, this is also an acidic buffer.
• The strongest acid out of the following is HCOOH.

 

 

• The stronger the acid, the stronger will be the buffer solution.
• From the table above, we see that oxalic acid which is a dibasic acid has the lowest Pka value and is the strongest acid among them.

<br>

Hence, the buffer solution of strong acidic nature is ${\rm{H}}_2{{\rm{C}}_2}{\rm{O}}_4^ + {{\rm{C}}_2}{\rm{O}}_4^{2 - }$.

Concept:

IUPAC nomenclature:

• A systematic method of naming organic compounds.
• Naming is based on their structures.
• It is devised by the International Union of Pure and Applied chemistry.
• Many rules are followed while naming the compounds and it is different for different functional groups.
• The rules are known as IUPAC rules.

Explanation:

• The priority of the functional groups is decided first.
• The sequence is given as follows:

​

• So, in the given compound

\(\begin{array}{{20}{c}} {{\rm{C}}{{\rm{H}}_3}}\ {}\ {} \end{array}\begin{array}{{20}{c}} { - {\rm{CH}}}\ |\ {{\rm{;;C}}{{\rm{H}}_3}} \end{array}\begin{array}{*{20}{c}} { - {\rm{C}}{{\rm{H}}_2} - {\rm{C}}{{\rm{H}}_2} - {\rm{Cl}}}\ {}\ {} \end{array}\)

• The numbering of the longest carbon chain in the compound is done starting from the carbon attached to the Chlorine atom.
• The longest chain has four carbon atoms and a methyl substituent at the 3^rd carbon atom so the parent alkane chain will be 3-methyl butane.
• There is a chlorine substituent at 1 position so the prefix will be 1- Chloro.

Hence, the IUPAC name of the compound thus becomes 1-chloro-3-methylbutane.

CONCEPT:

• Power: Power is the amount of energy transferred or converted per unit time.
• The SI unit of power is the watt (W), equal to one joule per second.
• Power is a scalar quantity.
• Dimensional formula of power: [M L² T^-3]

​1 Joule (J)/second (Sec) = 1 Watt (W)

Power (P) = Work done (W)/time (t)

Where P = power in watt, W = work in joule, t = time in second.

CALCULATION:

Given that:

Energy consume = 1200 joules/min = 1200 J/min

1 min = 60 sec.

P = 1200 J/min = 1200/60 J/sec = 20 J/sec

P = 20 watt.

Concept:

• Natural killer cells are known for their “natural” ability to lyse tumour cells and virus-infected cells without prior sensitization.
• Natural killer cells are an important component of the innate immune system that comprises 10% to 20% of circulating lymphocytes.

Explanation:

• Natural killer cells do not resemble from T and B lymphocytes as they lack expression and rearrangement of the T cell receptor and surface immunoglobulin.
• Natural killer cells can lyse target cells through 2 mechanisms, either by perforin-granzyme mediated cytolysis or by induction of target cell apoptosis by Fas ligand. Natural killer cells can also mediate antibody-dependent cellular cytotoxicity (ADCC) through interaction with surface receptor.

Additional Information

• The immune system may be of two types innate and acquired. Innate immunity (immunity by birth) and acquired immunity (adaptive immunity which uses T-cells and B-cells).
• T cells and B cells are the cellular components of the adaptive immune response. T cells are involved in cell-mediated immunity, whereas B cells are primarily responsible for humoral immunity (relating to antibodies).

Concept:

Apparent weight of a person inside a lift

(i) When the lift moves upward with acceleration a. Then the net upward force on the person is-

R - mg = ma

∴ Apparent weight, R = mg + ma = m (g + a)

So, when a lift accelerates upwards, the apparent weight of the person inside it increases.

(ii) When the lift moves downwards with acceleration a. Then the net downward force on the person is-

Mg - R = ma

∴ Apparent weight, R = mg - ma = m (g - a)

So, when a lift accelerates downwards, the apparent weight of the person inside it decreases.

(iii) When the lift is at rest or moving with uniform velocity v downward/upward. The acceleration a = 0, then the net force on the person is-

R - mg = m x 0 = 0

R = mg

∴ Apparent weight = Actual weight

(iv) When the lift falls freely. If the supporting cable of the lift breaks, the lift falls freely under gravity. Then a = g. The net downward force on the person is -

R = m(g - g) = 0.

Thus, the apparent weight of the man becomes zero. This is because both the man and the lift are moving downwards with same acceleration ‘g’ and so there are no forces of action and reaction between the person and the lift. Hence a person develops a feeling of weightlessness when he falls freely under gravity.

Explanation -

When the lift moves downward with acceleration a -

Then the net upward force on the person is-

Mg - R = ma

∴ Apparent weight, R = mg - ma = m (g - a)

This is a reason why one feels lighter in a lift when the lift just begins to go down because our body starts moving in same direction as gravitational force hence there is less opposition on our body hence net force exerted on our body is less as compared to when lift was going up.

Thus, when a lift accelerates downward at constant acceleration, the apparent weight of the person inside it decreases at constant rate also.

Concept:

• Bacteriophages were discovered by Frederick W. Twort in 1915. D Herelle coined the term bacteriophage, meaning bacteria eater.
• The bacteriophage is called phage; a group of viruses that infect bacteria.
• Phages are simple organisms that consist of a core of genetic material (nucleic acid) surrounded by a protein capsid. The nucleic acid may be either DNA or RNA and may be double-stranded or single-stranded.
• In QB - bacteriophage - ss RNA is present.
• In ϕ X 174 - bacteriophage - ss DNA is present.

Explanation:

• During infection, a phage attaches to a bacterium and inserts its genetic material into the cell. After that, a phage usually follows one of two life cycles, lytic (virulent) or lysogenic (temperate).

<br>

So, the lysogenic cycle of a phage allows replication of the phage genome without destroying the host.

Concept:

Isomers:

• These are compounds that have the same molecular formula but different structures or stereochemistries.
• There is a wide range of classification of organic molecules based on their structures.

​

Ring -Chain isomers:

• Ring chain isomerism is a type of structural isomerism.
• It is shown by compounds that are capable of forming stable ring compounds. The minimum number of carbons that must be present in order to show ring chain isomerism is three.
• The phenomenon of a compound existing in open-chain as well as ring form is called ring chain isomerism.
• Cyclic compounds formed by rings of 3,4,5,6 carbon atoms are called propane, butane, pentane hexane respectively.

Explanation:

• Pentene has the formula C₅H₁₀ and it can form three, four, and five-membered ring compounds.
• The cyclic isomers of pentene with their names are given as follows:

Additional Information

• The open-chain isomers of pentane are:

The number of isomers and the carbon atoms are given below:

Explanation:

• Sickle cell anaemia is an inherited red blood cell disorders in which there are not enough healthy red blood cells to carry oxygen throughout your body.

• Haemoglobin (Hb) is the iron-containing oxygen-transport metalloprotein in the red blood cells of the blood in vertebrates and other animals.
• Normal haemoglobin is called haemoglobin A, but people with sickle cell disease have only haemoglobin S, which turns normal, round red blood cells into abnormally curved (sickle) shapes.
• Disease is caused by a point mutation in the ß-globin chain of haemoglobin, replacing the amino acid glutamic acid with the less polar amino acid valine at the sixth position of the ß chain.

So Sickle-cell anaemia glutamic acid is replaced by valine amino Acid.

Additional Information

• Normally RBCs are discs like shapes, which give them the flexibility to travel through even the smallest blood vessels. However, in sickle cell anaemia, the RBCs have an abnormal crescent shape resembling a sickle.
• Red blood cells usually live for about 120 days but sickle cells usually die in 10 to 20 days, and chronic anaemia caused by excessive destruction of the abnormal red blood cells.

Concept:

Haloform Reaction: 

• Acetaldehyde and all methyl ketones can be oxidized by hypohalite solutions to yield a haloform (chloroform, bromoform, or iodoform) and the reaction is called haloform reaction.
• A yellow ppt. of iodoform is seen.

The general reaction scheme is given as follows 

R-COCH₃ + X₂/OH(hydroxide) = RCOO^- + CHX₃ (halo form)

\(\begin{array}{{20}{c}} {\rm ,,,,,,O}\ {,,,,,,||}\ {\rm C{H_3} - C - R } \end{array} \begin{matrix} {} \\ {} \\ \xrightarrow{\rm 3NaOH} \end{matrix} \ \ \begin{array}{{20}{c}} {\rm ,,,,,,O}\ {,,,,,,||}\ {\rm C{H_3} - C - R } \end{array} \begin{matrix} {} \\ {} \\ + \ \ \rm 3NaOH \end{matrix} \)​

\(\begin{array}{*{20}{c}} {\rm ,,,,,,O}\ {,,,,,,||}\ {\rm C{X_3} - C - R } \end{array} \begin{matrix} {} \\ {} \\ \rm \xrightarrow{NaOH} \underset{haloform}{CHX_3} + RCOONa \end{matrix} \)

Explanation:

Criteria for giving positive haloform test:

• All compounds containing CH3 –C=O and CH3CH-(OH) groups are positive to the Haloform test.
• Also, the compounds which on oxidation with halogen and alkali yield CH3 -C=O groups will respond positively to Haloform Test.
• Common compounds that respond to this test are
• CH3CH2OH
• CH3CHO
• CH3COCH3
• CH3COC2H5
• CH3CHOHCH3.

​Step I (oxidation step)

\(\begin{array}{{20}{c}} {\rm C{H_3} - CH - R + {I_2}}\ {|,,,,,,,,,,}\ {\rm OH,,,,,,} \end{array} \begin{matrix} \begin{array}{{20}{c}} {\rm \ \ \ \ \ O,,,,,,,}\ { \ \ \ \ \ ||,,,,,,,}\ {\longrightarrow \rm C{H_3} - C - R + 2HI} \end{array} \\ {} \\ {} \\ {} \\ {} \end{matrix}\)

2.Halogenation.

\(\begin{array}{{20}{c}} {\rm O,,,,,,,}\ {||,,,,,,,}\ {\rm C{H_3} - C - R + 3{I_2}} \end{array} \begin{array}{{20}{c}} {\rm \ \ \ \ O,,,,,,,}\ { \ \ \ \ ||,,,,,,,}\ {\longrightarrow \rm C{I_3} - C - R + 3{HI}} \end{array} \)

3. Hydrolysis

\(\begin{array}{{20}{c}} {\rm C{I_3} - C - R + {NaOH}}\ {||, \ \ \ \ \ \ \ \ \ \ ,,,}\ {\rm O,,,,,, \ \ \ \ \ \ \ \ } \end{array} \begin{matrix} \begin{array}{{20}{c}} {\rm \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ O,,,,,,,}\ { \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ||,,,,,,,}\ {\longrightarrow \rm \underset{Iodoform}{C{HI_3}} + R - C - ONa } \end{array} \\ {} \\ {} \\ {} \\ {} \end{matrix}\)

• 2-degree alcohols on oxidation produce CH3C=O-- group as shown above and thus reacts positively to haloform test.

Thus, both the groups \(\begin{array}{{20}{c}} {\rm O,, \ \ ,,,,,,,}\ {|| \ \ ,,,,,,,,,,}\ { - \rm C - C{H_3}} \end{array}\) and \(\begin{array}{{20}{c}} {\rm OH,,,,,, \ \ \ ,,}\ {|,,,,,,,,, \ \ \ \ ,,,,}\ { - \rm{CH - CH}_3} \end{array}\)will give the haloform test.

Hence, (CH3)2CHOH will give a positive iodoform test.

Concept:

• Chromosomes are long thread-like structures that have DNA organized and packed & secured in the nucleus.
• Through chromosomes, genetic information is carried from one generation (parents) to another generation (offsprings). Chromosomes are necessary for all life processes like  Replication, Protein synthesis, Cell division, etc.

• The diagram shows the structure of chromosomes.

Explanation:

• Chromosomes are structures present in the nucleus of a cell composed of genetic material (DNA) wrapped around some proteins ( histones & non Histones).
• Every species has a specific number and pattern of the chromosome. it is called the genotype of that species.
• The human genotype has 23 pairs of chromosomes. out of which 22 pairs are autosomes and 1 pair is called as Allosomes or Sex chromosomes.
• Two types of sex chromosomes are present in Humans, X & Y.
• ​The human male carries XY pair as sex chromosomes.
• The human Y chromosome is shorter than X chromosome. It can recombine with X chromosomes excluding some parts of its structure which are known as the Non-Recombining region of the Y chromosome [ NRY] at the telomer.

Since the tips of the Y chromosome do not combine with the X chromosome, thus these tips of the Y chromosome are known as pseudoautosomal regions (pseudo- False, autosomal- like autosomes).

Concept:

• Digestion is defined as, the process by which the complex, non-diffusible, and non-absorbable food substances are converted into simple, diffusible, nd assimilable substances.
• The human digestive system begins at the mouth. Teeth are part of the digestive system.
• 32 teeth are present in the buccal cavity of an adult human being.
• Human dentition is described as thecodont, diphyodont and heterodont.
• It is called thecodont type because each tooth is fixed in a separate socket present in jawbones by gomphosis type of joint.
• In our lifetime, we get only two sets of teeth, milk teeth and permanent teeth.
• This is called diphyodont dentition.
• We have four different types of teeth hence we are Heterodont.
• Types of teeth are incisors (I) canines (C) premolars (PM) and molar (M). Each half of each jaw has two incisors, one canine, two premolars,and three molars.
• Thus, the al formula of the adult human can be represented as,

Explanation:

• Molars are the teeth present at the rearmost part of our mouth ( buccal cavity ). the main function of molars is the grinding of food.
• There is a total of 12 molars present in the human buccal cavity.
• These molars are present in 3 sets each set comprising of 4 teeth.
• The first permanent molar erupts approximately at the age of 9-11 years and the second set of molar teeth erupt at the age of 12- 14 years.
• The third set of molar teeth are also called wisdom teeth that usually erupt in adulthood causing discomfort.

Concept:

Optical Microscope:

• It is also referred to as a light microscope that uses visible light and a system of lenses to generate magnified images of small objects.
• There are two types of Optical Microscopes:
• Simple Microscope: Uses the optical power of a single lens or group of lenses for magnification
• Compound Microscope: Uses a system of lenses (one set enlarging the image produced by another) to achieve a much higher magnification of an object
• In an optical microscope, both eyepiece and objective lenses are convex in nature.
• The magnification of the microscope depends on the length of the tube, not on the focal length.

Explanation:

• There are two lenses, eyepiece, and objective.
• We observe through the eyepiece and the object is captured by the objective lens. 
  

The magnification of the microscope is given as 

$m = \frac{LD}{f_0f_e}$      ---(1)

• where L = length of the tube , D = minimum distance of distinct vision, which is 25 cm for the human eye
• f0 = focal length of the objective = 1 mm ,  fe = focal length of the eyepiece = 25 mm

→ But we don't have the value of L which is the length of the tube hence we can not find the magnification of the microscope due to insufficient information we have.

→ That's why option 3 is correct because we need more information to calculate the magnification.

Concept:

• Kirchhoff’s Voltage Law: The algebraic sum of voltage (or voltage drops) in any closed path of the network that is traversed in a single direction is zero.

 

Here, the assumed current I causes a + ve drop of voltage when flowing from +ve to – ve potential while – ve drop of voltage when a current flowing from – ve to + ve for the above circuit,

 If we apply KVL,

−V + I R₁ + I R₂ = 0

Power delivered by source (P) = V I

Explanation:

From above discussion

We can say that in KVL, the sum of voltage drop in any closed path in DC circuit is equal to zero.

Concept:

Paramagnetic materials:

• Small, positive susceptibility to magnetic fields
• These materials are slightly attracted by a magnetic field
• Paramagnetic properties are due to the presence of some unpaired electrons, and from the realignment of the electron paths caused by the external magnetic field
• Paramagnetic materials include magnesium, molybdenum, lithium, and tantalum.

Bond order:

• It is the number of bonds between two atoms.
• The bonding electrons being stable contributes to increasing the bond order.
• The antibonding electrons being unstable contributes to decreasing the bond order.

Bond order is given by

 \(\raise.5ex\hbox{$\scriptstyle 1$}\kern-.1em/ \kern-.15em\lower.25ex\hbox{$\scriptstyle 2$} {\rm{ }}\left( {{\rm{ }}{\bf{No}}.{\rm{ }}{\bf{of}}{\rm{ }}{\bf{bonding}}{\rm{ }} - {\rm{ }}{\bf{no}}.{\rm{ }}{\bf{of}}{\rm{ }}{\bf{antibonding}}{\rm{ }}{\bf{electrons}}} \right)\)

• For filling up of electrons, we need to follow the series: σ 1sσ1sσ2sσ 2sσ 2pzπ 2py = π 2px π 2py* = π 2pxσ 2pz.
• For molecules till nitrogen, there is a slight change in the M.O energy order: 
• σ 1sσ1sσ2sσ 2sπ 2py = π 2pxσ 2pz π 2py = π 2pxσ 2pz*​

Explanation:

• ​The M.O diagram of CO is

• From the M.O diagram of CO, we see that there are no unpaired electrons and the molecule is thus diamagnetic.

 

O2- molecule, the electronic configuration is:

 σ 1s2σ1s2σ2s2σ 2s2σ 2pz2π 2py2π 2px2 π 2py2π 2px1.

• There are 10 bonding and 7 antibonding electrons out of which one electron in antibonding orbital is unpaired.
• The unpaired electron makes it paramagnetic in nature.

The M.O of NO+ is as follows:

​

 

• From the M.O diagram of NO⁺, we see that there are no unpaired electrons and the molecule is thus diamagnetic.

If we construct the M.O diagram of CN, we will see that there are no unpaired electrons.

Hence, O₂^- is paramagnetic.

Additional Information

Diamagnetic materials

• Weak, negative susceptibility to magnetic fields
• Diamagnetic materials are slightly repelled by a magnetic field
• All the electrons are paired so there is no permanent net magnetic moment per atom
• Most elements in the periodic table, including copper, silver, and gold, are diamagnetic.

Concept:

• An ore is a body of rock that contains a high enough concentration of a metallic or non-metallic resource.
• Ores are extracted from the earth via mining and then treated to extract valuable minerals from them.

Explanation:

Slag:

• Slag is a product of Flux and impurity.
• Slag is a waste matter separated from metal during smelting and other metallurgical and combustion processes from impurities in the metals.
• The iron and silica is an example of slag that is removed during copper and lead smelting.
• In steel-making furnaces, during the separation of the molten steel from impurities produced steel slag.
• Slags are divided into two parts blast furnace slag and metallurgical slag.
• The slag consists mostly of mixed oxides of elements such as silicon, sulfur, phosphorus, and aluminum.​​

Flux:

• These are the substances used to remove impurities such as slag in metallurgical processes.
• Common examples of flux are silica, dolomite, lime, borax, fluorite, etc.

Gangue:

• Gangue can be described as the unwanted or worthless material impurities that surround an ore.
• Gangue is mixed with minerals in ores and needs to be separated.
• The separation of gangue from minerals is achieved via mineral processing.
• Mineral processing is a complicated process and often depends on the nature of minerals.
• For example, Froth Floatation Method is used for removing gangue from sulfide ores. This method employs a mixture of water and pine oil which is made to froth in a tank to separate sulfide ores.

Hence, the impurities associated with minerals used in metallurgy are collectively called gangue.

Explanation:

• RNA (Ribo Nucleic Acid) in a nucleic acid present in cells of living organisms.
• There are three types of RNA, as follows

Types of RNA

So, If all the tRNAs within a cell were suddenly destroyed, the translation would be directly and immediately affected.

Concept:

Fehling's test:

• It is an alkaline solution of CuSO4 and sodium-potassium tartrate.
• The aldehydes reduce Cu2+ to red cuprous oxide.

​

Halo form Reaction: 

 

• Acetaldehyde and all methyl ketones can be oxidized by hypohalite solutions to yield a haloform (chloroform, bromoform, or iodoform) and the reaction is called haloform reaction.
• A yellow ppt. of iodoform is seen.

The general reaction scheme is given as follows 

• R-COCH3+X2/OH(hydroxide)= RCOO^- +CHX3 (halo form)

​Nitroprusside test:

• This test can be used to distinguish between aldehydes and ketones.
• Ketones react with sodium nitroprusside to form a red-coloured complex whereas aldehydes do not.
• Sodium nitroprusside is Sodium pentacyano nitrosyl ferrate(III):

​

NaHSO3 test:

• Both aldehydes and ketones respond to this test.
• With sodium bisulphite, aldehydes and ketones form crystalline substances called aldehyde bisulphite and ketone bisulphite respectively.
• The reaction is given as follows:

​

Explanation:​

​Criteria for giving positive haloform test:

• All compounds containing CH3 –C=O and CH3CH-(OH) groups are positive to the Haloform test.
• Also, the compounds which on oxidation with halogen and alkali yield CH3 -C=O groups will respond positively to Haloform Test.
• Common compounds that respond to this test are
• CH3CH2OH
• CH3CHO
• CH3COCH3
• CH3COC2H5
• CH3CHOHCH3.​
• Formaldehyde and Propanal do not undergo haloform reaction.
• In Acetaldehyde, the CH3CO: keto methyl group is present so it will give a positive haloform test.

• Whereas in  C6H5CH2CHO, no keto methyl group is present. So, this will not yield haloform.

Hence, iodoform test is a suitable test for the distinction between CH3CHO and C6H5CH2CHO.

Important Points

• Fehling, Tollen's and Benedicts test are used to distinguish between aldehydes and ketones.

Concept:

• Motion under gravity: An object is falling freely with no forces acting upon it except gravity. Then the distance covered by the object is given by

 

${\rm{s}} = {\rm{ut}} + \frac{1}{2}{\rm{g}}{{\rm{t}}^2}$

Where s = distance travelled under gravity, u = initial speed, g = gravitational acceleration, t = time.

Calculation:

Given mass of pizza = 3 kg, t = 2 s, g = 9.81 m/s²

${\rm{s}} = {\rm{ut}} + \frac{1}{2}{\rm{g}}{{\rm{t}}^2}$

u = 0, because pizza is falling from rest.

${\rm{s}} = 0 \times 2 + \frac{1}{2}9.81 \times {2^2}$

s = 9.81 × 2 = 19.62 m

s = 19.62 m

Key Points

• In Electron Transport Chain (ETC), the electrons are transferred through a series of carriers located in the inner mitochondrial membrane.
• The ETC in mitochondria comprises of different protein complexes that act as electron carriers:
• Complex I - is NADH dehydrogenase that transfers electrons from NADH to Coenzyme Q (Ubiquinone).
• Complex II - is succinate dehydrogenase that transfers electrons from succinate (TCA cycle intermediate) to coenzyme Q via FADH₂.
• Complex III - receives the electrons from coenzyme Q, passes it from cytochrome b to cytochrome c and ultimately to complex IV.
• Complex IV - is cytochrome oxidase that carries electrons from cytochrome c to molecular oxygen, reducing it to H₂O.
• Complex V - is ATP synthase that has the F₀ and F₁ components that are responsible for driving the phosphorylation reaction of ADP to form ATP.

Explanation:

• The electron transfers are coupled with proton transport from the matrix outwards through the complexes I, III and IV.
• This creates a proton gradient across the inner mitochondrial membrane.
• As the proton concentration becomes lower in the matrix, the pH of the matrix increases.
• The proton gradient forms a pH gradient as well as electric potential, which forms an electrochemical gradient together and drives the protons back into the matrix from cytosol.
• The ATP synthase complex acts as a protein channel for the protons to move through as the membrane itself is impermeable to ions.
• As the protons move through the F0 component, the F1 component undergoes rotation that drives ATP synthesis.

Additional Information

• NAD+ is oxidised - INCORRECT
• ​NAD+ is an oxidising agent that accepts electrons.
• Therefore, it gets reduced and NOT oxidised.
• ATP synthase pumps protons by active transport - INCORRECT
• ​It is not active transport as the proton transfer takes place from higher to lower proton concentration.
• Here, ATP synthase acts as a proton pump to produce ATP.

Concept:

• The human skeleton is the internal framework of the human body.
• The skeletal system is composed of the bones and joints in the body.
• The adult human skeletal system includes 206 bones.

Explanation:

• Male skulls are heavier, the bone is thicker and the areas of muscle attachment are more defined than in females, whereas women had smaller skulls than men.
• The length of the femur is an important and reliable skeletal element for sex determination.
• Women have greater hip-width, which influences the position of the femurs, which are found more angled and of a slight X shape than men.
• The human pelvic bone is the most reliable means for determining the sex of skeletal remains.
• The female pelvis is designed to offer optimal space for the birth canal, so females have wider pelvises, which are necessary for childbirth.
• So Vertebra bone is not helpful in determining the sex of a human.

Additional Information

Difference Between male and female Skeleton:

Concept:

Mitosis is a process where a single cell divides into two identical daughter cells (cell division).

Mitosis is divided into five phases.

• Crossing over occurs during meiosis I, in which homologous chromosomes often exchange chromosome part in a process called recombination. Crossing over re-arranges the combination of alleles within a chromosome, thus adding to the potential genetic variation found between individuals

Explanation:

Additional Information

Interphase is the preparatory stage, when the cell grows, replicates its DNA and prepares for mitosis.

Concept:

Microscope:

• The instrument having a double convex lens with a short focal length that produces an enlarged image of a small object is called a microscope.
• The microscope has two convex lenses- one of them is called an objective lens and another one is known as the eyepiece.

 

The magnification (M) of a microscope is given by:

\({\rm{M}} = \frac{{\rm{L}}}{{{{\rm{f}}0}}}\left( {\frac{{\rm{D}}}{{{{\rm{f}}{\rm{e}}}}}} \right)\)

Where, L = length of the microscope, D = least distance of clear vision, f₀ = focal length of objective and f_e is the focal length of the eyepiece

Explanation:

• Magnifying power of a microscope

\({\rm{M}} = \frac{{\rm{L}}}{{{{\rm{f}}0}}}\left( {\frac{{\rm{D}}}{{{{\rm{f}}{\rm{e}}}}}} \right)\)

Where f₀ = focal length of objective and f_e is the focal length of the eyepiece

${\rm{M;}}\frac{1}{{{{\rm{f}}_0}}}$

Thus if f₀ increases, then magnification of microscope will decrease.

Magnifying power of telescope 

\({{\bf{m}}{\bf{t}}} = - \frac{{{{\bf{f}}{\bf{o}}}}}{{{{\bf{f}}_{\bf{e}}}}}\)

⟹ m_t µ f_o

Thus if f_o is increased, then m_t will increase.

Concept:

Metal activity series:

• The metals are arranged in an activity order that is known as the metal activity series.
• The more active metals are present at the top of the series whereas the less active metals are put at the end of the series.
• The metal activity series is as follows-

​

Importance of the series-

• The metal activity series is used to predict displacement reactions.
• Metals that are above hydrogen in the series can displace hydrogen from acids.
• Metals that are below hydrogen in the series cannot displace hydrogen from the acids
• Metals that are higher in the activity series can displace metals that are lower to them from their salts.
• For example, zinc can displace copper from a solution of copper sulfate because zinc is above copper in the activity series.

Explanation: 

• Some metals have the characteristic reaction that they can liberate hydrogen from acids.
• Metals that are above hydrogen in the series of activity are able to displace hydrogen from the acids.
• However, metals below hydrogen are not able to do so because they are less reactive.
• Some acids such as nitric acid, are strong oxidizing agents, and some metals instead of undergoing displacement reactions, undergo oxidation.
• Al, Fe, and Cu all react with Cold dilute HNO₃ to undergo oxidation.

The reactions thus follow:

8Al + 30HNO₃ → 8Al(NO₃)₃ + 3N₂O + 15H₂O

Fe + 4HNO3 → Fe(NO3)3 + NO

Mg + 2HNO3 → Mg(NO3)₂ + H₂

Cu + HNO3 → Cu(NO3)₂ + NO + H2O

• Thus, only Mg is liberating hydrogen with cold dilute nitric acid.

Hence, metal Mg evolves hydrogen on reaction with cold dilute HNO3.

Concept:

• Photoelectric effect: When the light of a sufficiently small wavelength is incident on the metal surface, electrons are ejected from the metal instantly. This phenomenon is called the photoelectric effect.

 

Explanation

In the given options

• Sodium, lithium, and magnesium are electropositive and they also lose electrons easily but their reactivity is much less than Caesium.
• Cesium is the most electropositive element of all so it has the minimum ionization energy and so contains the maximum capacity to lose electrons.

The correct answer is option 4.

Key Points

Alkali metals

• Alkali metals belong to the s-block elements occupying the leftmost side of the periodic table.
• Alkali metals readily lose electrons, making them the most reactive elements on earth.
• In general ‘alkali’ refers to the basic or alkaline nature of their metal hydroxides.
• The compounds are called alkali metals because when they react with water they usually form alkalies which are strong bases that can easily neutralize the strong acids.
• Alkali metals have a Noble gas electronic configuration (ns1).
• They occupy the first column of the periodic table.
• Alkali elements are Lithium(Li), Sodium(Na), Potassium (K), Rubidium (Ru), Cesium (Cs) and Francium (Fr).

Explanation:

• The electronegativities decrease from Lithium to Caesium.
• Alkali metals are all highly reactive and are never found in elemental forms in nature.
• They are usually stored immersed in mineral oil or kerosene (paraffin oil) because of their highly reactive nature.
• They have generally low melting points and densities.
• This is because the bonds which are present in the alkali metals are weak metallic bonds.
• The strength of the metallic interaction is much weaker than van der Waals's forces.
• Thus, the heat required to separate them is not high and they melt easily at low temperatures.
• As we move down the group, the atomic weights of the alkali metals increase, and with the increase of atomic weight, the metallic bonding also decreases.
• The decrease in the extent of metallic bonding leads to a decrease in melting point.
• The trend of melting point is: Li > Na > K > Rb > Cs.

Hence, with the increase in atomic weights, the melting points of the alkali metals decrease.

Additional Information

• Different groups have different trends in boiling points, in some, it increases whereas in others it decreases.
• For example, generally melting and boiling points of halogens and Noble gases increase down a group.
• While moving along a period from left to right, the boiling point first increases and then decreases.

Concept:

• Quartz is a crystalline compound that contains mainly SiO2 (Silicon dioxide).
• It can be found in igneous, sedimentary as well as metamorphic rocks.
• Quartz can be further of many types depending on the trace elements present in it.
• Quartz melts at approximately 1600°C and forms a tacky liquid.
• Many silicon-oxygen bonds are broken in the course of melting.
• Quartz glass is also known as silica glass since it is obtained by melting silica.
• Quartz is piezoelectric material because it contains silicon.

Explanation:

Sheet silicate:

• The major components of silicates are SiO₄^4- tetrahedrons. The center has silicon and four oxygen atoms are placed at the four corners of the tetrahedron.
• Sheet silicates are formed by sharing of three bridging oxygen atoms per silicon atom resulting in a 2-D framework.
• Mica, Chlorites, talcs, serpentines are examples of sheet silicates.

​Cyclic silicate:

• Cyclic silicates contain  SiO44^- units joined in a cyclic manner.
• Two oxygen atoms are shared between each of the units.
• Example of cyclic silicate is Bentonite.

Framework silicate:

• In framework silicates, all the four oxygen atoms are shared, forming SiO₂ units in between.
• The SiO44^- and SiO2 units are present in the ratio 1:2.
• Framework silicates are generally aluminosilicates with the exception of quartz.
• Quartz is a framework silicate having no aluminium.
• The framework silicates have the given structure:

 

Chain silicate:

• They are formed by linking n units of SiO44-  tetrahedron linearly.
• They can be single chain as well as double chain.

​Hence**, quartz** is an example of framework silicate.

Additional Information

Piezoelectric materials:

• These materials produce an electric spark when mechanical stress is applied to them.
• The piezoelectric effect was demonstrated in 1880 for the first time by Pierre Curie and Jacques Curie

Concept:

• DNA is made of nucleotides monomer which is joined together by covalent bonds between the phosphate group of one nucleotide and the third carbon atom of the pentose sugar in the next nucleotide.
• These nucleotides are made of three parts: a phosphate group, a pentose sugar, and one of four types of nitrogen bases.
• Nitrogen bases are of two types. The purines in DNA are adenine and guanine, which is the same in RNA. The pyrimidines in DNA are cytosine and thymine, whereas in RNA, they are cytosine and uracil (in place of thymine).

Explanation:

• As the double DNA strand is complementary to each other, so in double-stranded DNA there is always.

G = C, and A = T.

(G-Guanine, C-Cytosine, A-Adenine, T-Thymine)

• Here in Question given percentage of G and C is equal and the percentage of A and T is equal so this nucleic acid must be double-stranded DNA.
• Thymine is only found in DNA.
• Thus the given percentage of nitrogen base, indicates that it is double stranded DNA.

Additional Information 

• Purines and pyrimidines nitrogen bases hold DNA strands together through hydrogen bonds.

• Thymine is only found in DNA, not in RNA. in RNA in place of thymine, Uracil is found.

Concept:

• The KE_avg of a collection of gas molecules is directly proportional to the temperature of the gas.
• Described by the equation:

 

${\rm{K}}{{\rm{E}}_{{\rm{avg}}}} = \frac{3}{2}{\rm{;RT}}$

Where R is the gas constant and T is the kelvin temperature

And

${{\rm{v}}_{{\rm{rms}}}} = \sqrt {\frac{{3{\rm{RT}}}}{{\rm{m}}}}$

So, v_rms µ T

Explanation:

${{\rm{v}}_{{\rm{rms}}}} = \sqrt {\frac{{3{\rm{RT}}}}{{\rm{m}}}}$

In the closed rigid container, the speed of the air molecules is directly proportional to the temperature of the system.

Concept:

• DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication process uses DNA polymerase III to catalyzes the joining of deoxyribonucleoside 5′-triphosphates (dNTPs) at a growing chain of DNA.
• DNA is read by DNA polymerase in the 3′ to 5′ direction, meaning the new strand is synthesized in the 5' to 3' direction.

Explanation:

• In the DNA replication process, one new strand (leading strand) is made as a continuous piece. The other (lagging strand) is made in small pieces.
• At the leading strand, DNA polymerase III synthesizes the new strand in the 5′ to 3′ direction.
• The lagging strand is elongated in an antiparallel direction, by the addition of short RNA primers (Okazaki fragment) which are filled with other joining fragments.
• As explained above during DNA replication RNA Primer is removed by DNA polymerase I.

Additional Information

• DNA replication is semiconservative, meaning that each strand in the DNA double helix acts as a template for the synthesis of a new, complementary strand.
• DNA Polymerase I possess a 3´→ 5´ exonuclease activity or "proofreading" function, which lowers the error rate during DNA replication.

Other Important Enzyme in DNA Replication

Confusion Points

• DNA polymerase III extends the primers, adding on to the 3' end, to make the bulk of the new DNA.
• DNA polymerase I remove RNA primers and replaced them with DNA.

Concept:

• A virus is a small parasite that cannot reproduce by itself. Viruses contain a nucleic acid core, enclosed with a protein capsid. After infection of a susceptible cell, a virus can direct the cell machinery to produce more viruses.

Explanation:

• A virus attaches to a specific receptor site on the host cell membrane through attachment proteins glycoproteins, which is found embedded in the viral envelope. The specificity of this interaction determines the host and the cells within the host that can be infected by a particular virus. Some of these glycoproteins are Hemagglutinin, neuraminidase in the influenza virus. Thus Glycoprotein play important role in the control of viral infections.
• A Riboprotein is basically a complex of ribonucleic acid and RNA-binding protein. These complexes play an integral part in a number of important biological functions that include transcription, translation and regulating gene expression and regulating the metabolism of RNA.
• Lipoprotein are the constituents of viral envelopes, which surrounds the viruses helical core and forms the membranes of two lipid layers interspersed with protein molecules (lipoprotein bilayer).

Additional Information

• The viral envelope is made up of a lipid bilayer (lipoprotein) embedded with viral glycoproteins.
• This receptor-binding Glycoprotein protein has an α-helical transmembrane domain that spans the viral envelope, and a short internal domain. The internal domain interacts with the viral matrix protein, which functions as a bridge between the transmembrane glycoprotein and nucleocapsid protein. Fusion of viral and cell membranes is driven by specialized viral glycoproteins, called fusogens.

Concept:

Oxidation reaction:

• Oxidation Reaction refers to a reaction in which either the addition of Oxygen takes place or the removal of Hydrogen takes place.
• It can also be said as the process of loss of one or more electrons by atoms or ions.
• Example is:

Mg + O2 = Mg2O

• Acids come from the word 'Acidus' which means sour.
• Acids have a sour taste.
• Acids are substances that can furnish proton H+ in solution.
• They are good conductors of electricity.

Explanation:

Wine:

• Wine is a type of alcoholic drink.
• Wine is prepared by the fermentation of sugar present in grapes with the help of yeast.
• Grapes are the most important raw material for the preparation of wine.
• The yeast converts the sugar via fermentation into ethanol and carbon dioxide.

Glucose + Yeast → Ethyl alcohol + CO₂

• The alcohol when left under air, is oxidized by aerobic bacteria to the corresponding acid.
• So, ethanol when left open gets converted to ethanoic acid or acetic acid.
• The taste of acids is sour and thus the wine also turns sour.
• The following reaction takes place:

C2H5OH + O₂ →  CH3COOH

Hence, when wine is put in the air, it becomes sour due to the oxidation of C2H5OH to CH3COOH.

Additional Information

• The production of alcohol in these beverages is mainly focused on the fermentation of yeast.
• Yeasts are eukaryotic microorganisms that ferment a variety of sugars from different sources into the final products of carbon dioxide and alcohol.
• Yeasts are the primary fermenter and alcohol producer in the manufacture of wine, beer, and other alcoholic beverages.
  

Saccharomyces cerevisiae is the key yeast species used.

• It ferments sugars from various sources, e.g. grapes for wine, barley for beer, alcohol and carbon dioxide.