VII. Answer the following questions. Use all information given before.

1. What is sensitivity?

2. What do all animal nervous systems consist of?

3. Why are ductless glands called so?

4. What is the difference between sense organs and effectors?

5. What is CNS? What does it consist of?

6. What are two major systems that convey information in mammals?

VIII. Find English equivalents to the following word combinations and make up sentences with them:

N	Russian term	English equivalent
1.	главным образом, в основном
2.	передача нервных импульсов
3.	состоять из чего-либо
4.	находиться где-либо
5.	железы внутренней секреции
6.	выделять гормоны
7.	нервные волокна
8.	передавать информацию
9.	мозг человека
10.	содержать, заключать (в себе)
11.	реагировать соответственно, должным образом
12.	одноклеточный
13.	благоприятный
14.	ограниченное число / небольшое количество чего-либо

IX. Read and translate the short text without any dictionary

Fact of life:

Most nerve fibres are very thin (less than 10 um in diameter), but the giant nerve fibre of a squid may be more than 1 mm across.

X. Food for thought.

Squids can escape from danger because they have giant nerve fibres. These fibres can conduct nerve impulses very rapidly, since speed of conduction is directly related to the diameter of the fibre. Squids have nerve fibres of normal diameter to control their slow cruising movements, but giant nerve fibres control their rapid escape response. When danger threatens, giant nerve fibres carry information from the brain down the body, causing circular muscles to contract and force a jet of water out of the body, enabling the squid to make a quick backward escape.

Suggest why squids have giant nerve fibres only for rapid escape responses. Why do mammals not require giant nerve fibres?

XI. Prepare a short presentation on 2 or 3 glands reflecting the following issues:

• Type of gland, its position

• Type of hormone, its function

• Role of the hormone in human health

17. Text 5.2. Setting up a nerve impulse

■ Essential targets:

By the end of this text you should be able to:

• explain how a resting potential is maintained

• explain how an action potential is generated.

Pre-reading

■ Discuss these questions with your partner. Then compare your ideas with the information given in the text.

1. What do you know about the nature of nerve impulses?

2. Why are nerve impulses important for humans?

■ Read the following text and make your essential assignments: