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Key Points

 Jodhpur:

• Jodhpur is also known as 'Blue City' or 'Sun City' as the houses are blue painted in the old area of the city.
• Jodhpur is a popular tourist destination, featuring many places, forts and temples, set in the stark landscape of the Thar Desert.
• Jodhpur is also said to be the cultural capital of Rajasthan state.

​​Thus, Sun city is the name of Jodhpur.

Additional Information

Concept:

Hormone:

• Hormones are non-nutrient chemicals which act as intercellular messengers and are produced in trace amounts.

Explanation:

Thus, the correct match is (i) - (b), (ii) - (d), (iii) - (a), (iv) - (c)

Concept:

Mahatma Gandhi:

• Mahatma Gandhi has been regarded as the 'Father' of the Indian nation.
• In India, Gandhi Jayanti is observed to commemorate Mahatma Gandhi's birth on 2^nd October.

Self sufficient:

• Mahatma Gandhi’s ideas about self-sufficiency and handicrafts were directly related to his views on industries and industrial society.
• Gandhiji believed that industrial societies were based on an endless production of commodities.

Explanation:

Khadi:

• Khadi is a hand-spun and -woven natural fibre fabric that Mahatma Gandhi promoted as swadeshi (self-sufficiency) for the Indian subcontinent's freedom struggle.
• He encouraged people to wear clothes made of homespun yarn termed khadi.
• The Sabarmati Ashram produced the first item of the hand-woven fabric in 1917–18.
• Cotton is used to make the fabric, but it may also contain silk or wool, both of which are spun into yarn on a charkha.
• On Gandhi Jayanti(means,2^nd October), the government announced a  discount on khadi products.

Thus, on 2^nd October a special discount is provided on the price of the clothes made up of Khadi.

Additional Information26 January:

• Indian Constitution came into effect on 26 January 1950.
• It is known as the Republic day of India.

21 June:

• On June 21, people around the world witness International Yoga Day.
• To promote yoga in general and to educate people about its advantages.

5^th September:

• Every year on September 5, teachers' day is witnessed to honour Dr. Sarvepalli Radhakrishnan.
• Who were a celebrated educator and recipient of the Bharat Ratna award who served as India's first vice president and second president of India

Answer: Low air pressure

Concept:

Mountaineering:

• Mountain climbing, also known as mountaineering, is a sport.
• It involves reaching or making an effort to reach high points in mountainous terrain, primarily for enjoyment.

 Key Points

Low air pressure at high altitudes:

• One's body might not get enough oxygen when engaged in mountain climbing at a high altitude.
• The air becomes drier and less oxygenated as the altitude rises.
• The pressure needs to be higher outside one's body for someone's lungs to be able to breathe in air without resistance.
• However, at high altitudes, their lungs have to work harder to draw in the thinner air.
• one's veins have to work harder to pump oxygen throughout the body.
• This is because the outside air pressure is lower than the inside air pressure.

Thus, the main reason for the difficulty in breathing while mountaineering is low air pressure.

Additional Information Some other problems of mountaineering:

Steep slope:

• Areas that have a slope greater than a specific percentage are considered steep slopes.
• If the slope is steeper, there may not be enough friction and slipping.

Extreme cold weather:

• Hypothermia and frostbite are two additional problems that can arise when mountaineering in extremely cold temperatures.

Icy wind:

• Mountains experience stronger, colder, and more unpredictable winds.
• Climbing is dangerous in winds of 60 to 70 mph because there is a high likelihood of being knocked over and getting hurt.

Concept:

Ecosystem: 

• All organisms such as plants, animals, microorganisms and human beings as well as the physical surroundings interact with each other and maintain a balance in nature.
• All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem.
• The term ecosystem was coined by Tansley.

Explanation:

Components of an ecosystem:

Biotic Components: 

• It includes producers, consumers and decomposers.
• All living things have a direct or indirect influence on other organisms in an environment.
• Example: plants, animals, humans, microorganism etc.

Abiotic components: 

• All the in-organic components of the ecosystem, non-living physical and chemical composition of nature are abiotic components.
• Example: land, stones, water, humus (organic waste), air etc.

Thus, air comes under the abiotic component of the environment.

Silkworm:

• Silkworms eat only mulberry leaves.
• The entire process can be controlled by keeping the worms in a controlled environment.
• Protecting them from ants, mice, and disease; and feeding them mulberry leaves.
• Silkworms produce pupa by feeding on mulberry leaves.

Key Points

Mulberry leaves:

• The protein fibre of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons.
• The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity (sericulture).
• Silkworms are oligophagous insects, and mulberry leaves are their best food source.
• All nutrients and water silkworms need come from mulberry leaves.
• Which is a result of the long-term co-evolution and natural selection between silkworms and mulberry trees.

Thus, the food of silkworms is mulberry leaves.

Important Points

Sericulture:

• The method of raising silkworms and harvesting silk from them is known as sericulture.
• Domestic silkmoth caterpillars (also known as ‘Bombyx mori') are the most widely used silkworm species in sericulture.

Additional Information

Alkaloid:

• An alkaloid is a class of naturally occurring organic nitrogen-containing compounds that are frequently found in the plant kingdom.
• Many alkaloids are valuable medicinal agents that can be utilized to treat various diseases including malaria, diabetes, cancer, cardiac dysfunction etc.

​

Key Points

Tobacco:

• Tobacco has been used by human beings for more than 400 years.
• It is smoked, chewed or used as a snuff.
• Tobacco contains a large number of chemical substances including nicotine, an alkaloid.
• Smoking is associated with an increased incidence of cancers of the lung, urinary bladder and throat, bronchitis, emphysema, coronary heart disease, gastric ulcer, etc.
• Tobacco chewing is associated with an increased risk of cancer of the oral cavity.
• Smoking increases the carbon monoxide (CO) content in blood and reduces the concentration of oxygen in the blood.

Important Points Nicotine:

• It's a naturally occurring chemical that contains nitrogen.
• It is heavily addictive.

Uses

• Nicotine is used as a recreational drug because of its mood-altering and pleasure-inducing effects.o
• It is also used as a treatment for addiction to tobacco.
• It is also used as a pesticide.

Thus, Nicotine is an alkaloid found in tobacco.

Additional Information

Caffeine:

• Caffeine works by stimulating the central nervous system (CNS), heart, muscles, and the centres that control blood pressure.
• Caffeine can raise blood pressure, but might not have this effect on people who use it all the time.
• Caffeine can also act like a “water pill” that increases urine flow.
• It is found in tea and coffee.

Morphine:

• Morphine is a very effective sedative and painkiller.
• It is very useful in patients who have undergone surgery.
• Several plants, fruits and its seeds having hallucinogenic properties have been used for hundreds of years in folk medicine, religious ceremonies and rituals all over the globe.

Opioids:

• Opiates or drugs obtained from opium or artificially produced substitutes that have opium-like effects.
• They produce morphine-like effects.
• Medically they are primarily used for pain relief, including anaesthesia.
• Opioids are drugs, which bind to specific opioid receptors present in our central nervous system and gastrointestinal tract.
• Example: codeine, morphine, heroin.

Disease:

• A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism.
• It is not immediately due to any external injury.
• Diseases are often known to be medical conditions that are associated with specific signs and symptoms.

Key PointsRabies disease:

• Rabies is a viral disease that is spread through animal bites such as a dog.
• Rabies can affect both domestic and wild animals.
• It is caused by the infection of rabies virus  T.
• The infection caused by this leads to encephalomyelitis.
• It causes inflammation of the brain as well as the spinal cord.
• Rabies is a vaccine-preventable disease.
• Initial symptoms of rabies include a fever with pain and unusual or unexplained tingling, pricking, or burning sensation at the wound site.
• As the virus spreads to the central nervous system, progressive and fatal inflammation of the brain and spinal cord develops.

Important Points

Thus, Rabies disease is caused by viruses.

Additional InformationProtozoa:

• Disease brought on by protozoans or protozoal sickness.
• Although many of these organisms complete part of their reproductive cycle in insects or other hosts, some may live their whole lives inside the human host.

​Bacteria:

• Bacteria are microorganisms that come in various shapes.
• They can be spheres, they can be rods, or they can be spirals.
• There are bacteria that are bad, which we call pathogenic, and they cause diseases.

Mycoplasma:

• Mycoplasma is a genus of bacteria that, like the other members of the class Mollicutes, lack a cell wall around their cell membranes.
• Peptidoglycan (murein) is absent.
• This characteristic makes them naturally resistant to antibiotics that target cell wall synthesis

Concept:

Pollution:

• Pollution is any undesirable change in physical, chemical or biological characteristics of air, land, water or soil.

Water pollution:

• Whenever harmful substances such as sewage, toxic chemicals, silt, etc, get mixed with water, the water becomes polluted.
• The substances that pollute water are called water pollutants.

Explanation:

Humus matter:

• Humification leads to the accumulation of a dark-coloured amorphous substance called humus.
• That is highly resistant to microbial action and undergoes decomposition at an extremely slow rate.
• Being colloidal in nature it serves as a reservoir of nutrients.
• The humus is further degraded by some microbes and the release of inorganic nutrients occurs through the process known as mineralisation.
• Crops such as wheat are grown in fine clayey soils because they are rich in humus and are very fertile.

Thus, humus matter is not a human source of water pollution. 

 Additional InformationSewage: 

• It is wastewater released by homes, industries, hospitals, offices and other users.
• It also includes rainwater that has run down the street during a storm or heavy rain.
• The water that washes off roads and rooftops carries harmful substances with it.
• Sewage is liquid waste including domestic and industrial wastewater that pollute water sources.

Concept:

Natural fibre:

• The fibres of some fabrics such as cotton, jute, silk and wool are obtained from plants and animals.
• These are called natural fibres.

Synthetic fibre:

• Fibres that are not obtained from plant or animal sources. These are called synthetic fibres.
• Some examples of synthetic fibres are polyester, nylon and acrylic.

Explanation:

Silk:

• Silk fibres are animal fibres.
• Silkworms spin the ‘silk fibres’.
• The rearing of silkworms for obtaining silk is called sericulture.
• The silk yarn (thread) is obtained from the cocoon of the silk moth.

The life cycle of the silk moth:

• The female silk moth lays eggs, from which hatch larvae, which are called caterpillars or silkworms.
• The next stage of its life history is called the pupa.
• During these movements of the head, the caterpillar secretes fibre made of a protein which hardens on exposure to air and becomes silk fibre.
• Then pupa turning into a moth continues inside the cocoon.

​Thus, silk is an example of fibre which is obtained from animals.

 

 

 

 

 

 

 

 

 

Additional InformationCotton:

• Cotton plants are usually grown in places having black soil and a warm climate.
• The fruits of the cotton plant (cotton bolls) are about the size of a lemon.
• Fibres are then separated from the seeds by combing.
• This process is called ginning of cotton.

Polyester:

• Polyester is synthetic fibre.
• Fabric made from this fibre does not get wrinkled easily.
• It remains crisp and is easy to wash.

Nylon:

• Nylon is man-made fibre.
• It was made without using any natural raw material (from plants or animals).
• It was prepared from coal, water and air.
• Nylon fibre was strong, elastic and light.