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Q1. What adaptation helps the tiger in catching its prey?

Solution

The tigers skin is yellowbrown in colour. It helps the tiger to hide in the grass or in the forest as it waits to catch its prey. Tigers have sharp claws on their front legs which help them catch their prey.

Q2. Why different regions of earth have different climate?

Solution

Different parts of earth receive different amount of sunlight so different regions of earth have different climate. For example - equator receives perpendicular sun rays so the climate is hot and humid on equator.

Q3. Why the days are shorter in winter than in summer?

Solution

During summer, sunrise is early and the sunset is late. Due to this, days are longer in summers and nights are shorter. On the other hand, during winter the sunrise is late but the sunset is early. Due to this, days are shorter in winter but the nights are longer.

Q4. How has the toucan adapted to the tropical rainforests?

Solution

The toucan has a long, large beak to reach the fruits on branches which are otherwise too weak to support its weight. It is capable of changing the colour of its feathers in order to blend with the surroundings. 

Q5. Why Siberian crane migrates in winters?

Solution

Siberian crane migrates to India in winter to avoid chilling temperature of Siberia.

Q6. Name the countries which fall in the polar regions.

Solution

Canada, Greenland, Iceland, Norway, Sweden, Finland, the state of Alaska in USA and the Siberian region in Russia represent the polar regions.  

Q7. Why monsoon winds bring rainfall to India?

Solution

Monsoon winds blow from Arabian sea and Bay of Bengal to Indian landmass. These winds carry water vapours with them so they cause rainfall in India.

Q8. Does the amount of humidity change in the same day?

Solution

Yes, the amount of humidity changes in the same day because as the temperature increases the rate of evaporation increases and vice versa.

Q9. Polar bears move slowly and rest very often. Explain why.

Solution

Polar bears are well insulated by two thick layers of fur and a layer of fat under the skin which protects them from the cold and keeps them warm. To avoid overheating due to all this insulation, they move slowly and rest often.

Q10. Why is it said that the climate of Rajasthan is hot and dry?

Solution

The temperature in Rajasthan is high for most part of the year, and it receives very little rainfall. So, it is said that the climate of Rajasthan is hot and dry.

Q11. Why windward side of mountain receives heavy rainfall?

Solution

When moisture laden winds meet a range of mountains, they get pushed up. As they climb, they cool and the moisture condenses to bring rainfall.

Q12. Weather of a place along the sea coast and that of a place up in the mountains is not the same. Explain.

Solution

The Sun is the primary source of energy, and all changes in weather occur due to it. The weather of a place depends on the energy absorbed and reflected by the surface, the atmosphere and the water bodies present. Hence, the weather is not the same along the sea and up in the mountains.

Q13. Why mangroves are found in coastal region?

Solution

Mangrooves are able to survive in salty water so they are found in coastal regions.

Q14. Why coastal areas have moderate temperature?

Solution

Coastal areas have moderate temperature because the land absorbs and radiates heat much faster than sea. So, during the day cool air from sea rush towards the land and during night cool air from the land rush towards sea.

Q15. How does temperature and humidity become causative factors for rainfall?

Solution

When the air is close to being saturated and suddenly temperature falls so some of the vapours condense and thus cloud formation takes place. Small droplets join together and become heavy and come down as rain.

Q16. Why nights are foggy during winters?

Solution

In winters when temperature falls after sunset, water vapour condenses near the ground .The droplets hanging in the air form fog so, nights are foggy in winters.

Q17. Why mosses are best suited for polar regions?

Solution

Mosses are short lived flowering plants. They complete their life cycle in short summer period. So they are well suited for polar regions.

Q18. Name some animals living in the polar regions.

Solution

Seal, musk deer, reindeer, arctic fox, different types of fish and birds live in the polar regions.

Q19. Why India has a warm tropical climate?

Solution

India is located near equator in the tropical region so India has warm tropical climate.

Q20. Why deciduous trees shed their leaves during autumn season?

Solution

Deciduous trees grow in tropical regions during autumn season. As there is shortage of water so to cope up with this condition they shed their leaves.

Q21. What is the main outstanding feature of lion tailed macaque?

Solution

Its main outstanding feature is the silver white mane, which surrounds the head from the cheeks down to its chin.

Q22. How have the penguins adapted themselves to the polar regions?

Solution

Penguins are birds which are found in the Southern Hemisphere or the southern pole. Penguins have a thick skin and layers of fat to protect them against the cold. They move in groups to keep themselves warm. They have streamlined bodies and webbed feet which make them good swimmers.

Q23. What is climate?

Solution

The climate of a place is the average weather pattern over a long period of time.

Q24. What is weather?

Solution

The day-to-day conditions of the atmosphere at a place with respect to the temperature, humidity, rainfall and wind speed is called the weather of that place.

Q25. We feel comfortable and warm in the afternoon during winters but feel cold or chilly in the morning or evening. Why?

Solution

The temperature of a place is maximum in the afternoon and reduces as the day progresses, reaching a minimum during the night and in the morning. So, we feel warmer in the afternoon and chilly in the mornings during winters.

Q26. How animals avoid competition for food in rainforests?

Solution

Animals feed in different layers of forests to avoid competition for food. For example - Gorillas live on forest floor and birds and monkeys live on branches of trees and feed there .

Q27. Name the countries where tropical rainforests are found.

Solution

Tropical rainforests are found in the Western Ghats and Assam in India, and in Malaysia, Indonesia, Brazil, Republic of Congo, Kenya, Uganda and Nigeria.  

Q28. What are the different elements of weather?

Solution

Humidity, rainfall, temperature and wind speed are different elements of weather.

Q29. Why rainforests have variety of organisms?

Solution

Climate of rainforests is tolerable as it has hot and humid climate. So, a large variety of animals and plants are found there.

Q30. When is air considered saturated?

Solution

When air holds the highest amount of water vapour at a given temperature, air is then said to be saturated at that temperature.

Q31. How and why is the climate of Jammu and Kashmir different from that of Assam?

Solution

The climate in Jammu and Kashmir is moderately hot and wet, while Assam mostly has a wet climate. Assam gets rain most of the time as compared to Jammu and Kashmir.

Q32. How has the red-eyed frog adapted to the tropical rainforests?

Solution

The red-eyed frog has sticky pads on its feet which help it to climb the trees on which it lives. Also, its green skin helps it to hide in the leaves of trees and remain unnoticed by its prey.

Q33. Why evergreen forests are found in equatorial region?

Solution

Equatorial region has hot and wet climate which is good for growth of various types of plants and animals.

Q34. Why does relative humidity change over a day?

Solution

Relative humidity of a place changes over a day because earth does not receive equal amount of heat throughout the day.

Q35. Why India has a warm tropical climate?

Solution

India is located near equator in the tropical region so India has warm tropical climate.

Q36. Why the days are shorter in winter than in summer?

Solution

During summer, sunrise is early and the sunset is late. Due to this, days are longer in summers and nights are shorter. On the other hand, during winter the sunrise is late but the sunset is early. Due to this, days are shorter in winter but the nights are longer.

Q37. What produces weather?

Solution

Weather is produced by the heat of the sun and the effect it has on the atmosphere.

Q38. The lion-tailed macaque rarely comes down to the ground. How does it get its food?

Solution

The lion-tailed macaque or the bearded ape feed on fruits, seeds, young leaves, stems, flowers and buds. It also sometimes eats insects found under the bark of trees. It gets its fill of food on the trees. So, it rarely comes down to the ground.

Q39. How have elephants adapted to the tropical rainforests?

Solution

Elephants use their trunk as their nose due to which they have a strong sense of smell. The trunk also helps the elephants in picking up food. The tusks of the elephant are modified teeth. They help them tear the bark of trees which is eaten as food. The large ears help the elephant to hear soft sounds. The ears also help the elephant to keep cool in the hot and humid rainforest climate.  

Q40. (i) Why the maximum and minimum temperature of cities is higher than in rural areas?(ii) Why does relative humidity change over a day?

Solution

(i) 1.Concrete ground absorbs more heat in comparison to soil and retains it for a longer time. 2.Urban areas lack shade of trees. 3.Cooling effect in urban areas is relatively less due to less transpiration effect of plants.(ii) Relative humidity of a place changes over a day because earth does not receive equal amount of heat throughout the day.