Environmental Studies PYQs

Concept:

The earth is round there is actually no 'up' and 'down' on the earth and it is just relative. 

Explanation:

• The earth can be divided into two hemispheres, the upper (northern hemisphere) and the lower (southern hemisphere).
• They are just names for specific places on the Earth so that it is easy for us to give directions and find our way around.
• These hemispheres are relative if not defined clearly.
• An equator is used to divide the earth into two hemispheres.
• For example for a person staying in Sydney, he/she can consider themselves in the northern hemisphere, then India will be in the southern hemisphere.
• Meanwhile, for a person staying in Delhi, Sydney will lie in the southern hemisphere. Everything is relative.
• If Earth was upside down and no one would really notice, because one would still feel that the ground is down and the sky is up.
• This is because gravity always pulls us towards the middle of the Earth.
• Argentina is a country in the southern half of South America on one side of the equator most commonly referred to as the southern hemisphere.
• Whereas India lies on the other side of the equator in the Asian sub-continent most commonly referred to as the northern hemisphere.

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​Thus, we, the people of India, actually stand upside down in relation to the people of Argentina.

• Libya, Algeria, and Alaska (USA) all lie above the equator in the same hemisphere (i.e northern hemisphere) as that of India.
• Thus, there is no relative difference in location between these countries and India.

The correct answer is an urban or metropolitan area that is warmer than its surrounding rural areas. 

Key Points 

Urban heat islands:

• An urban heat island (UHI) is an urban area or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities.
• The temperature difference is usually larger at night than during the day and is most apparent when winds are weak. UHI is most noticeable during the summer and winter.
• An urban heat island occurs when a city experiences much warmer temperatures than in nearby rural areas.
• The difference in temperature between urban and less-developed rural areas has to do with how well the surfaces in each environment absorb and hold heat.
• The main cause of the urban heat island effect is the modification of land surfaces.
• Waste heat generated by energy usage is a secondary contributor.
• As a population center grows, it tends to expand its area and increase its average temperature.
• The term heat island is also used; the term can be used to refer to any area that is relatively hotter than the surrounding but generally refers to human-disturbed areas.

Causes of formation:

• Dark surfaces
• Thermal mass
• Lack of vegetation
• Waste heat
• Changing climate

Effects:

• Urban deserts: cities can be thought of as virtual deserts with almost no vegetation and materials that are almost completely impermeable to rain.
• Urban canyons: the tall canyons formed by city buildings trap radiant energy in their walls. Comparisons of this "canyon effect" in European and North American cities suggest that areas with denser and taller buildings will more rapidly develop heat islands.
• Urban haze: The haze of air pollution that hangs over many cities can act as a miniature greenhouse layer, preventing outgoing thermal radiation (heat) from escaping from urban areas.
• Anthropogenic heat: The release of heat from the burning of fossil fuels can also raise urban temperatures.

Key Points 

Virus:

• Viruses are the smallest organisms and consist of genetic material (DNA or RNA) enclosed in a protein coat.
• They are much smaller than bacteria, ranging in size from about 20 to 300 nanometers (nm).
• Viruses are considered non-living as they require a host cell to reproduce and cannot carry out metabolic activities independently.

Bacteria:

• Bacteria are single-celled organisms that are larger than viruses.
• They are typically measured in micrometers (µm) and range in size from about 0.2 to 10 µm.
• Bacteria are diverse and can be found in various environments, including soil, water, and living organisms.
• They have a variety of shapes, such as rods (bacilli), spheres (cocci), and spirals (spirilla).

Algae:

• Algae are larger than bacteria and can vary in size depending on the species.
• They are typically measured in micrometers (µm) to millimeters (mm).
• Algae can be single-celled or multicellular organisms and are photosynthetic.
• They use sunlight and chlorophyll to produce energy and can be found in aquatic environments, including oceans, lakes, and ponds.

Fungi:

• Fungi are generally larger than bacteria and algae.
• They consist of multicellular organisms, although some fungi can be unicellular.
• The size of fungi can vary greatly, ranging from micrometers (µm) to centimeters (cm).
• Fungi include a wide range of organisms, such as molds, yeasts, mushrooms, and mildews.
• They obtain nutrients through absorption and play important roles in decomposing organic matter and forming symbiotic relationships with other organisms.

In summary, the order of organisms in ascending order of size is Virus (smallest) - Bacteria - Algae - Fungi (largest).

Concept:

• Indian women have had some success at the World Weightlifting Championships.
• Kunjarani Devi, Karnam Malleswari, Lalita Polley, Bharti Singh, Neelam Setti Laxmi, and Saikhom Mirabai Chanu are the winners who secured medals at the said tournament.

Explanation:

Karnam Malleswari:

• Karnam Malleswari (born June 1, 1975, in Srikakulam, Andhra Pradesh) is an Indian weightlifter.
• Her father is a police constable.
• Malleshwari started lifting weights when she was 12 years old.
• Now she can lift a weight of 130 kilograms.
• Karnam has won 29 medals in international events.
• Her four sisters also practise weight lifting.
• During her ten years career, she has won 11 gold and three silver medals besides the prestigious Olympic bronze.
• She has been the National Champion for nine years (twice in the 52 kg category and seven times in the 54 kg category).
• It is notable that on September 19, 2000, Malleswari in the 69 kg weight class, lifted 240 kg to win the Sydney Olympic Bronze medal.
• She became the first woman athlete to win a medal in the Olympics.
• She is a recipient of the Rajiv Gandhi Khel Ratna award, India's highest sporting honour for the year 1995-1996.
• She is also a recipient of the civilian honour Padma Shri in 1999.
• Malleswari is awarded the Arjuna Award in 1994, India's second-highest award in sports.

Thus, in the chapter ‘Hu tu tu, Hu tu tu’ Karnam Malleshwari is a weight-lifter.

Concept:

• Direction is divided into 8 sections, 4 cardinal directions, and 4 ordinal directions.
• The four cardinal directions are the directions north, east, south, and west, commonly denoted by their initials N, E, S, and W.
• East and west are perpendiculars (at right angles) to north and south.
• East is in the clockwise direction of rotation from north and west is directly opposite east.
• The ordinal directions are northeast (NE), southeast (SE), southwest (SW), and northwest (NW).
• NE, SE, SW, and NW lie in between the cardinal directions north and east, south and east, south and west, and north and west respectively.

Diagram:

Thus, with respect to the examination centre the railway station is in the South-East direction.

The Correct Answer is: A, B and D

Concept:

• Animals have different senses.
• The animal world is full of examples of amazing senses.

Key Points

Tiger: 

• ​A tiger can see six times better at night than most of us.
• A tiger not only has yellow and black fur on its body but also has yellow and black stripes on its body.
• The tiger’s whiskers are very sensitive and can sense the movements or vibrations in the air.
• A tiger’s sense of hearing is so sharp that it can make out the difference between the rustling of leaves and the sound of an animal moving on the grass.
• The ears of the tiger can move in different directions and this helps to catch the sounds from all around.
• Tigers make different sounds for different purposes like when it is angry or to call out to a tigress. It can also roar or snarl.
• Tigers mark their area with their urine.
• A tiger can at once come to know if there is another tiger in its area by the smell of the urine.
• A lion's roar can be heard up to 3 km away.​

Thus,

A. Tiger’s whiskers help them to move in dark and find its prey: Correct 

B. Ears of tigers can move in different directions: Correct 

C. Tiger’s roar can be heard up to 5 kilometers away: Incorrect 

D. Tiger’s marks their own area, which covers several kilometers, with urine: Correct 

Additional Information 

Animals and their super senses: 

Vulture:

• Vultures can see four times as far as we can.
• These birds can see things from a distance of eight metres what we can see from a distance of two metres.

Silkworm: 

• Some male insects can recognise their females by their smell.
• Silkworms can find their female worm from many kilometres away by her smell.

Dog: 

• Dogs mark out their own area on the road.
• They can make out if another dog has come into their area by the smell of its urine or potty (latrine).

Concept: 

• Time taken for journey = Arrival time - Departure time
• Speed = Distance/Time
• When a person travels two equal distances with different speeds, let X km/h and Y km/h
• Average speed = 2XY/(X + Y) km/h

Explanation:

• Total time taken = 7^th September 21:45 hours to 9^th September 9:15 hours = 35.5 hours
• Total distance travelled = 2055 km
• Average Speed = 2055/35.5 km/hr = 57.88 km/hr = 57.8 km/hr​​​

Thus, the average speed of the journey is 57.8 km/hr

Chennamma's statement about her grandma feeding grains to birds in the temple suggests that she is linking classroom learning to outside the school and also displaying natural curiosity about the natural environment.

Key Points

• Chennamma is connecting the information she learned in the classroom to a real-life situation outside of school.
• In the story, the gardener stops birds from entering the garden, leading to an increase in insects and a decrease in mangoes.
• Chennamma recalls her grandma feeding grains to birds in the temple, which suggests that she recognizes a different perspective or scenario where birds are not necessarily eating insects but are being provided with grains.
• This demonstrates her ability to apply classroom knowledge to real-world situations.
• Chennamma's comment about her grandma feeding grains to birds also indicates her natural curiosity about the natural environment.
• She is questioning and observing the behavior of birds and their diet.
• This curiosity reflects an interest in understanding the relationships between animals and their environment, showcasing a genuine interest in the world around her.

Hence, we can conclude that A and D is the correct answer.

The thematic approach used in EVS (Environmental Studies) for classes III to V is due to the nature of EVS being interdisciplinary.

Key Points

• Interdisciplinary refers to the integration and interaction of knowledge and approaches from multiple disciplines or subject areas.
• EVS is designed to provide students with a holistic understanding of the environment and its various aspects, including social, cultural, scientific, and ecological dimensions. It combines knowledge from different disciplines such as biology, geography, social sciences, and more to explore environmental issues and solutions.
• By adopting a thematic approach, EVS allows students to explore topics and issues in a comprehensive manner, considering various perspectives and connections between different subject areas.
• This approach encourages students to develop a broader understanding of the environment and its interconnectedness, fostering critical thinking, problem-solving, and a holistic approach to environmental issues.

Thus, it is concluded that a thematic approach has been used in EVS for class III to V instead of a topic-based approach due to interdisciplinary nature of EVS.

Summative assessment is an evaluation method that is typically conducted at the end of a learning period, such as at the end of a semester or school year.

Key Points

• Summative assessment's primary purpose is to assess students' learning outcomes and determine their level of achievement or proficiency in a particular subject or course.
• It is considered as a landmark for passing or failing students.
• It is focused on making judgments about students' overall performance and assigning grades or determining their level of success in a course or program.

Thus, it is concluded that Summative assessment is considered as a landmark for passing or failing students.

Based on the information provided, the facts mentioned in the chapter "A Snake Charmer's Story" of class V EVS indicate the following:

Key Points

• Interrelationship of plants, humans & animals: The snake charmers collect plants from the forests to make medicines, highlighting the connection between plants and humans. Additionally, the fact that snakes eat rats in the field to protect crops shows the interrelationship between animals (snakes) and humans (farmers).
• Interdependence of plants, humans & animals: The reliance on plants for medicinal purposes and the role of snakes in controlling the rat population in the field illustrate the interdependence between plants, humans, and animals.

Each component plays a vital role in maintaining a balanced ecosystem and fulfilling certain needs.

• Mutual dependence of plants, humans & animals: The snake charmers rely on plants for medicinal purposes, humans benefit from the medicinal properties of these plants, and snakes play a role in pest control to protect crops. This indicates a mutual dependence among plants, humans, and animals, where each entity relies on the others for certain benefits or functions.

Thus, it is concluded that A,B, and C is the correct answer.

The author is trying to relate Jhumpa's reaction of saying "Sssee, Sssee, Sssee" when tasting something to the experience of the child.

Key Points

• ​Each child's experience of tasting different foods is shaped by their individual preferences, sensitivity, and prior experiences.
• Jhumpa's "Sssee" might represent her way of expressing a strong taste sensation, reflecting her individual experience as a child.
• Sensory exploration is certainly a key aspect of the chapter and Jhumpa's experience, the author could also be using her reaction to highlight the unique and personal nature of taste perception.

Thus, it is concluded that the experience of the child is the correct answer.