Q.1. Which of these is specifically an adaptation for cold climates?

(a) blubber

(b) sweating

(c) long ears

(d) streamlined bodies

Ans: (a) blubber

Seals, which are found in cold climates, have a thick deposition of fat called blubber that protects them from cold.

Q.2. Which of these adaptations does a camel have for living in a desert?

(a) drinks and stores large quantity of water at a time

(b) very little sweating

(c) large soles on feet

(d) all of these

Ans: (d) all of these

The various adaptations present in a camel are as follows:

(i) Camel drinks a very large quantity of water at a time.

(ii) It sweats and urinates very little that helps to conserve water.

(iii) Its feet have large soles that are suitable for walking on desert sands.

(iv) It has a hump that helps to store large amounts of fat.

Q.3. Which of the following is true for the Poles?

(a) 12-hour day; 12-hour night

(b) about 18-hour day; about 6-hour night

(c) 6-month day with the sun high up in the sky; 6-month night

(d) 6-month day with the sun just above the horizon; 6-month night

Ans: (d) 6-month day with the sun just above the horizon; 6-month night

At the Poles, there is 6 months of day and 6 months of night, and the sun remains barely above the horizon during the 6-month day.

Q.4. Camouflage as an adaptation is found in

(a) hot climates

(b) cold climates

(c) hot and wet climates

(d) all climates

Ans: (d) all climates

The whiteness (white fur) of polar bear, which is found in cold climates, camouflages with the white snow and makes it difficult to be seen. Similarly, several animals found in hot and wet climates have a skin colour that camouflage with the background.

Q.5. Which of these is not an element of weather?

(a) temperature

(b) sun

(c) humidity

(d) rainfall

Ans: (b) sun

Temperature, humidity and rainfall are the elements of weather. Sun is not an element of weather.

Q.6. In which part of India can the climate be said to be hot and wet?

(a) Jammu and Kashmir

(b) Nagaland

(c) Kerala

(d) Rajasthan

Ans: (c) Kerala

The climate of Jammu and Kashmir is moderately hot and wet. The climate of Nagaland is wet. The climate of Kerala is very hot and wet. The climate of Rajasthan is hot and dry.

Q.7. Which of these does not affect the climate of a place?

(a) longitude

(b) distance from sea

(c) distance from mountains

(d) winds

Ans: (a) longitude

The following factors determine the climate of a place:

(i) Distance from the equator (latitude)

(ii) Height above the sea level

(iii) Distance from the sea or from the high mountain ranges

(iv) Direction of the wind

(v) Humidity in the air

Q.8. In which type of climate can you not expect to see reptiles?

(a) hot and dry

(b) very cold

(c) hot and wet

(d) hot and humid

Ans: (b) very cold

During the day, reptiles keep their bodies warm by absorbing the solar radiation. At night, they seek shelter to keep their bodies warm. However, this is not possible in polar regions, which has a very cold climate. Therefore, we do not expect to see reptiles in very cold climate.

Q.9. The temperature of a place is maximum during, the afternoon. True or false?

Ans: True.

The maximum temperature of the day at a given place occurs normally in the afternoon as the earth gets heated by the sun.

Q.10. Sun rays heat more near the equator because they are slanting. True or False?

Ans: False.

The heat produced by the sun's rays is more near the equator because the rays fall vertically.

Q.11. There is intense competition for food in the tropical rainforests because there is very little food. True and false?

Ans: False.

There is a constant supply of water and availability of a wide variety of food in tropical rainforests. The intense competition is because tropical rainforests support a large number of animals.

Q.12. In a city in the tropical region, the climate is expected to be ________ and ___________

Ans: In a city in the tropical region, the climate is expected to be warm and humid.

Q.13. In a desert, the climate is __________ and ___________

Ans: In a desert, the climate is hot and dry.

Q.14. Fur keeps an animal warm by trapping __________

Ans: Fur keeps the animal warm by trapping air.

Q.15. Birds living in the Polar Regions __________ to warmer regions in winters.

Ans: Birds living in the polar regions migrate to warmer regions during winters.

Q.16. Animal living in __________ usually come out to look for food at night.

Ans: Animals living in hot climate usually come out to look for food at night.

Q.17. What changes from day to day–the weather or the climate?

Ans: The weather of a place changes on a day to day basis. Climate, on the other hand, represents the overall average weather pattern of an area for a long time and it does not change on a daily basis. 

Q.18. In general, does it become colder or warmer as the latitude increases? Give reasons.

Ans: Generally, an increase in the latitude results in a colder condition. Latitude refers to the distance of a place from the equator. The equator receives vertical solar rays and thus, regions that are closer to equator (low latitude) tend to be warmer. Places that are far from equator (high latitude) tend to receive slanting solar rays and a large amount of solar heat is absorbed by the thick atmospheric layer of these areas, which keeps these regions cool. 

Q.19. Can the weather be accurately predicted? Give reasons.

Ans: It is not possible to accurately predict the weather. This is because weather depends on a large number of factors and these factors are variable. The variations of these factors result in complex changes in weather patterns, which makes it difficult to accurately predict weather. 

Q.20. During which season do you expect the sun to rise late and set early in Delhi?

Ans: In Delhi, the sun is expected to set early and rise late in the winter season.

Q.21. In which part of the earth can you expect to find animals with small ears, tails and legs–in a cold place or in a warm place? Give reasons.

Ans: Animals with small legs, tails and ears are expected to be found in a cold place. This is because parts of body such as tails, leg and ears lose heat gradually and smaller legs, tails and ears prevent excessive heat loss from the body. This ensures that the organism survives in the cold temperatures. 

Q.22. You must have seen dogs panting. Is panting used to cool or warm the body?

Ans: Panting is used to cool down the body. It helps in circulating air through the body, which cools down the body temperature. 

Q.23. An elephant lives in a rainforest. How is the trunk of an elephant useful in the rainforest?

Ans: The trunk of an elephant allows an elephant to gather food. An elephant uses its trunk to gather leaves and fruits present on the trees. 

Q.24. The fur of a polar bear helps it in two ways. What are these?

Ans: The fur helps a polar bear in the following ways:

1. The fur acts as an insulator and prevents heat loss from the body of polar bear.

2. The fur also helps polar bear in camouflaging. The white colour of fur helps the polar bear helps it to blend with the surroundings to avoid predators and catch prey. 

Q.25. What are the scientists who study the weather called?

Ans: Scientists who study the weather are called meteorologists.

Q.26. Does it become warmer of cooler when one goes up from sea level?

Ans: The higher one goes up from sea level, the cooler it becomes.

Q.27. Name four elements of weather.

Ans: The four elements of weather are temperature, humidity, rainfall and wind.

Q.28. Why is it very difficult to predict the weather?

Ans: Weather is affected by many factors and therefore very difficult to predict.

Q.29. Give an example to show how winds affect the weather.

Ans: Delhi becomes very hot during summers as the wind blows from the hot desert of Rajasthan towards Delhi.

Q.30. How does 'huddling' help penguins?

Ans: Huddling helps penguins to keep themselves warm.

Q.31. In general, what kind of climate do place near the sea have?

Ans: Places near the sea generally have a moderate climate; that is, neither very cold nor very hot.

Q.32. A polar bear has to move slowly, otherwise its body will get overheated. Why?

Ans: The polar bear has to move slowly; otherwise, its body will get overheated, because they have two thick layers of fur, as well as a layer of fat, under the skin which provide excellent insulation, and more physical activity can overheat their body.

Q.33. Explain the difference between weather and climate

Ans:

Q.34. What factors does the climate of a place depend on?

Ans: The climate of a place depends on the following factors:

(a) Distance from the equator

(b) Height above the sea level

(c) Distance from the sea or from the mountain ranges

(d) Direction of the wind

(e) Amount of humidity in the air

Q.35. Why is it cooler in regions further away from the equator?

Ans: It is cooler in regions further away from the equator because as the distance of a place from the equator increases, the sun's rays become more and more slanting. Slanting rays spread over a larger land area than vertical rays. Also, they pass through a thicker layer of the atmosphere which absorbs a large part of their heat. In contrast, the sun's rays near the equator fall vertically and heat the earth more.

Q.36. List three ways in which a polar bear is adapted to living in the Polar Regions.

Ans: A polar bear gets adapted to living in the polar regions in the following three ways:

(a) The body of a polar bear is covered with two thick layers of fur, as well as a layer of fat under the skin, which provides excellent insulation.

(b) The white fur of a polar bear camouflages with the white snow, protects it against the predators and helps it to catch its prey.

(c) A polar bear can close its nostrils and remain underwater for a long duration.

Q.37. Name one animal that lives on trees in rainforests and rarely comes down. How does it get its food?

Ans: Lion-tailed macaque, also known as beard ape, lives on trees in rainforests and rarely comes down. It mainly eats fruits and other plant parts. It also catches insects from under the bark of trees. It gets all the food it needs on trees.

Q.38. List three ways in which the elephant is well adapted to living in a tropical rainforest.

Ans: The following are the three ways in which the elephant is well adapted to living in a tropical rainforest:

(a) It has a strong sense of smell because it uses its long trunk as a nose.

(b) It uses its trunk to pull down fruits and leaves to eat.

(c) It uses its long ears to hear even soft sounds and to cool itself in the hot and humid climate.

Q.39. When do you expect wet clothes to dry faster-in dry weather or in humid weather? Why?

Ans: We expect wet clothes to dry faster in dry weather because there will be more evaporation of water in clothes in dry weather than in humid weather. With more evaporation of water, clothes will dry faster in dry weather.

Q.40. From where do the southwest monsoon winds pick up humidity?

Ans: South-west monsoon winds pick up humidity from the Indian Ocean and Bay of Bengal.

Q.41. Which days do you think are usually the longest and shortest in the southern hemisphere?

Ans: In the southern hemisphere, the longest day is 22 December and the shortest day is 21 June.

Q.42. During the course of the year, the length of the day changes. How do the times of sunrise and sunset change between summer and winter? Why does this happen?

Ans: The times of sunrise and sunset change as the Earth's axis is tilted when it moves around the sun. Hence, the position of the Sun changes during summer and winter. In summers, the Sun rises early and the day length increases; while in winters, the Sun rises late and the day length decreases.

Q.43. For thousands of years the human population on the earth increased very slowly.

(i) In the year 10,000 BCE, the estimated population was 50 million.

(ii) In 1700 CE, the population was only about 1 billion. Then it started accelerating very fast.

(iii) In 2000 CE, it had crossed 6 billion.

(iv) By 2050 CE, it is expected to cross 9 billion. What do you think has caused the huge increase?

Ans: There are various reasons due to which there has been a tremendous increase in the population -

(i) better adaptability to our surroundings

(ii) better developed resistance to diseases

(iii) proper healthcare facilities

(iv) advancements in technology

Q.44. List three adaptations in animals to prevent heat loss from the body, giving one example for each case.

Ans: Following are the adaptations in animals to prevent heat loss from the body:

(a) Polar bears and other mammals  hibernate during the winter months to reduce loss of heat.

(b) Penguins huddle together to keep themselves warm.

(c) Reptiles keep their body warm by absorbing solar radiation during the day and seeking shelter during the night.

Q.45. List three adaptations in animals which keep their body cool, giving one example for each case.

Ans: Animals adapt the following methods to keep their body cool:

(a) Fennec fox, which lives in desert, has very large ears. The ears have blood vessels near the surface. The air blowing across the ears cools the blood, which, in turn, cools the body.

(b) Porcupines and other nocturnal animals living in hot climates spend the daylight hours hiding in shady places such as burrows. They come out at night to look for food.

(c) Some animals living in hot climates sweat, pant and lick to cool themselves. The sweat or saliva evaporates to cool their bodies.