2.7 Read and correct the sentences:

1. Deserts are home to plants only.

2. The huge saguaro cactus draws up salt from the ground and releases it onto its leaves.

3. The road runner has long ears, which help to keep the animal from overheating.

4. Mammals tend to lie in the sun all day long.

5. Only the humps and nostrils help the camel not to sink into the sand.

2.8 Speak on a) the variety and plant and animal life in deserts; and b) how some desert plants and animals manage to survive in the harsh conditions of the desert.

2.9 Before reading the text given below check the meaning and the pronunciation of the words in the dictionary.

Endothermic, heat, tissue, skin, rangy, resting, goosebumps.

2.10 Match the words in A with their meanings in B:

A B

Monotremes сумчатые

Marsupials зимняя спячка

Hirbernation яйцекладущие

2.11 Match the words and phrases in A with their meanings in B.

A B

To heat To make or become hot or warm

To cool To give out sweat

To break down (food) To make or become cool

To supply (energy) To live or exist longer

To insulate To reduce to constituent parts

To sleek To cover or protect (a thing) with a

substance that prevents something of the loss of heat

To sweat To make sleek by smoothing

To pant To give or provide with something

To pull erect To breathe with short quick breaths

To shiver To stand on end, upright, vertical

To survive To tremble slightly especially with cold

or fear

To torpor To be in a sluggish and inactive condition

2.12 Read the text about mammals and answer the questions. Mammals

A mammal is an endothermic, “warm-blooded”, animal whose body is “heated from inside” and stays much the same temperature, no matter how hot or cold the surroundings.

When a mammal’s body breaks down food and oxygen in order to build new tissue and to supply energy, heat is produced. Hair, which grows out of the mammal’s skin, and fat, which lies under it, help insulate the mammal’s body against heat loss.

If the mammal becomes too hot, it cools itself by sleeking down its hair, sweating, panting or moving to a cool place. If the mammal becomes too cold, goosebumps pull its hair erect, it shivers to make extra body heat, and moves to a warmer place.

Monotremes have a normal body temperature of 30 degrees C. Marsupials average 35 degrees C, while human (which is also a mammal) body temperature is normally about 37 degrees C.

Desert mammals often have big ears and rangy bodies. The large skin area loses heat fast.

Mammals which live in cold places have compact bodies and thick fur. Insulating fat beneath their skin can be used by the body as a food source in very cold weather.

Some animals, like small bats and echidnas, survive cold by going into a short-term resting state called torpor, or a longer “sleep” called hibernation.

2.13 Answer the questions:

1. Why is a mammal an endothermic animal?

2. How is heat produced in the mammal’s body?

3. What does the mammal do if it’s too hot or too cold?

4. Is the body temperature of monotremes different from that of marsupials?

5. Why do desert animals often have rangy bodies?

6. What kind of bodies do mammals living in cold places have?

7. Why do they insulate fat beneath their skins?

8. How do some animals survive in cold?