2021-22 SCIENCE CH 7 Weather, Climate and Adaptations of Animals to Climate(NB AND WB EXERCISE)

2021-22 SCIENCE CH 7 Weather, Climate and Adaptations of Animals to Climate(NB AND WB EXERCISE)

NEW WORDS                     H.W

serrated

camouflage

papillae

migration

meteorologists

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NEW TERMS

Blubber: thick deposits of fat under the skin of animals of the polar regions 

 Camouflage: an adaptation in animals that helps them to hide or disguise their presence

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Answer the following questions in short. 

a. What is climate? 

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

b. Define the term weather. 

ANS. Weather is the atmospheric condition of a particular place over a short period of time. Weather encompasses the natural events happening in the atmosphere each day. It is about the changes that take place in the atmosphere at a given place and time.

 c. How does blubber help a polar bear? 

ANS. The polar bear has a thick layer (about 10 cm thick) of fat under its skin known as blubber. This acts as an insulator protecting the bear from the extreme cold. In order to avoid getting overheated due to the two thick layers of fur and the blubber they move slowly and rest often.

d. How many layers are tropical rainforests composed of? Name the layers. 

ANS. A typical tropical rainforest consists of four layers as listed below:

1.Emergent layer

2.Canopy

3.Understorey layer

4.Forest layer

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 Give reason. 

a. Polar bears have a strong sense of smell. 

ANS. The polar bear is carnivorous and feeds mainly on seals as they have a lot of fat in their body. It can also eat walruses and fishes. A strong sense of smell helps them to catch the prey.

b. Siberian crane and Artic tern are known as migratory birds.

ANS. 

Birds that migrate seasonally are called migratory birds. Migratory birds store extra fat which acts as a source of energy helping them to fly long distances. The Arctic tern and the Siberian crane are examples of migratory birds. The Siberian crane migrates to Bharatpur in Rajasthan and Sultanpur in Haryana.

Siberian cranes migrate from Siberia, they arrive in December and stay till early March. (ii) Arctic Tern are also known for long yearly migration.

 c. Red-eyed frogs, open their eyes and display their bright colours when they are disturbed. 

ANS. They use the bright colours as a defence mechanism. 

If they are disturbed, they open their bright red-eyes and display their bright colours. 

Potential predators may be momentarily disturbed, confused, or frightened by the sudden appearance of these bright colours, giving the frog time to hop away.

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Answer the following questions in detail. 

a. Describe the adaptations seen in red-eyed tree frogs. 

ANS. Big, red, forward-facing eyes dominate their head. They have orange or red feet and blue inner thighs. 

 • They have sticky pads on their fingers and toes to grip the branches of trees and climb. 

 • The green colour helps them to hide in the leaves from both their prey and predators. 

 • They use the bright colours as a defence mechanism. If they are disturbed, they open their bright red-eyes and display their bright colours. Potential predators may be momentarily disturbed, confused, or frightened by the sudden appearance of these bright colours, giving the frog time to hop away.

 b. Explain the term adaptation. Name and explain the two types of adaptations. 

ANS. The changes in the body and behavior of organisms that enable them to survive in their environment are known as adaptations.

Structural Adaptations

Adaptations in the structural or physical features of an organism are known as structural adaptations. For example, the presence of fur on a bear to protect it against the cold.

Behavioral Adaptations

Behavioral adaptation is a change in the way an organism behaves or acts. Animal migration is an example of behavioural adaptation. Grey whales migrate to the warm water off the coast of Mexico from the cold Artic Ocean thousands of miles away every year.

 c. Describe how polar bears adapt to the polar regions.  

ANS. The body is covered with thick two layers of white fur to keep them warm. The colour of the fur helps them to camouflage themselves in the snow and thus protects them from predators and also helps them to catch their prey. 

 • The polar bear has a thick layer (about 10 cm thick) of fat under its skin known as blubber. This acts as an insulator protecting the bear from the extreme cold. In order to avoid getting overheated due to the two thick layers of fur and the blubber they move slowly and rest often. 

• The paws are covered with soft outgrowths called papillae. The papillae allow the polar bear to walk on ice and snow without slipping.

 • The polar bear carries out physical activities like swimming in order to keep themselves warm.

·       The polar bear is carnivorous and feeds mainly on seals as they have a lot of fat in their body. It can also eat walruses and fishes. A strong sense of smell helps them to catch the prey.

 

HOTS

Do you agree that rainforests plays an important role in the prevention of soil erosion and regulation of water flow? Give reasons for your answer. 

ANS. 

 

MIND MAP

 

WORKBOOK EXERCISEhttps://drive.google.com/file/d/1ZR_db3vmf5vCjN3zM8BKnj1RDqNUekK6/view?usp=sharing