Class seven science chapter 7 NCERT Solutions
N C E R T Textbook Questions Solved
1. Name the elements that determine the weather of a place.
Answer: The temperature, humidity, rainfall, wind-speed, etc. are called the elements that determine the weather of a place.
2. When are the maximum and minimum temperatures likely to occur during the day?
Answer: The maximum temperature of the day occurs generally in the afternoon and the minimum temperature occurs in the early morning.
3. Fill in the blanks:
(i) The average weather taken over a long time is called ______________.
(ii) A place receives very little rainfall and the temperature is high throughout the year, the climate of that place will be
______________ and ______________.
(iii) The two regions of the earth with extreme climatic conditions are ______________
and ______________.
Answers: climate of the place (ii) hot, dry (iii) polar, tropical regions
4. Indicate the type of climate of the following areas:
(a) Jammu and Kashmir: ______________
(b) Kerala: ______________
(c) Rajasthan: ______________
(d) North-east India: ______________
Answer:
(a) Jammu and Kashmir: Moderately hot and
moderately wet climate.
(b) Kerala: Very hot and wet climate.
(c) Rajasthan: Hot and dry climate.
(d) North-east India: Wet climate.
5. Which out of these two changes occurs frequently, weather or climate?
Answer: Weather occurs frequently.
6. Followings are some of the characteristics of animals:
(i) Diets heavy on fruits
(ii) White fur
(iii) Need to migrate
(iv) Loud voice
(v) Sticky pads on feet
(vi) A layer of fat under the skin
(vii) Wide and large paws
(viii) Bright colours
(ix) Strong tails
(x) The long and large beak
For each characteristic indicate whether it is an adaptation for tropical rainforests or polar regions. Do you think that some of these
characteristics can be adapted for both regions?
Answers:
Characteristics of animal’s adaption
(i) Diets heavy on fruits: Tropical rainforests
(ii) Need to migrate: Polar Regions
(iii) Sticky pads on fruits: Tropical rainforests
(iv) Wide and large paws: Polar Regions
(v) Strong tails: Tropical rainforests
(vi) Long and large beak: Tropical rainforests
(vii) White fur: Polar Regions
(viii) Loud Voice: Tropical rainforests
(ix) A layer of fat under the skin: Polar Regions
(x) Bright Colours: Tropical rainforests
7. The tropical rainforests have a large population of animals. Explain why it is so.
Answer: Because of continuous warmth and rain, the tropical region supports an enormous number and a wide variety of animals.
8. Explain with examples, why we find animals of certain kind living in particular climatic conditions.
Answer: Animals are adapted to survive in the conditions in which they live. Features and habits which help them to adapt to their surroundings are the results of evolution. So, to survive in a particular type of climate the animals must have certain adapted features. This is the reason we find animals of certain kind of living in particular climatic conditions. For example, animals in the polar region are adapted to the extremely cold climate. They have special characteristics, such as white fur, a strong sense of smell, a layer of fat under the skin, wide and large paws for swimming and walking in the snow, etc.
9. How do elephants living in the tropical rainforests adapt themselves?
Answer: The elephant has adapted to the conditions of rainforest in many remarkable ways. Elephants used their trunk as a nose that gave them a good sense of smell. They can also pick up food with the help of their trunk. In fact, they have very heavy trunks which can even break the bark of trees. Their large ears help in hearing even soft sounds
as well. They also help in keeping their body cool in the hot and humid climate of the rainforests.
Choose the correct option which answers the following question:
10. A carnivore with stripes on its body moves very fast while catching its prey. It is likely to be found in:
(i) polar regions
(ii) deserts
(iii) oceans
(iv) tropical rainforests
Answer: (iv)
11. Which features adapt polar bears to live in an extremely cold climate?
(i) A white fur, fat below the skin, keen sense of smell.
(ii) Thin skin, large eyes, a white fur.
(iii) A long tail, strong claws, white large paws.
(iv) White body, paws for swimming, gills for respiration.
Answer: (iv)
12. Which option best describes a tropical region?
(i) Hot and humid
(ii) Moderate temperature, heavy rainfall
(iii) Cold and humid
(iv) Hot and dry