Text A. THE BRAIN

Scientists consider that our brain is the most complicated mechanism which has ever been constructed. The brain lies in the biggest cavity of the skull which is called the cranial cavity. It is divided into three parts: the medulla, the forebrain consisting mainly of the cerebrum, and the cerebellum. The medulla (or the brain stem) is a portion of the spinal cord connecting it with the brain. The forebrain and the cerebellum are divided into two hemispheres which are connected by a thick band of nerve fibers. These hemispheres have areas called “lobes” which perform specific functions.

The weight of the human brain is from one to two kg. and it consists of about 12 billion (миллиард) cells. It has been determined by the scientists that each cell is connected to the other directly or indirectly by nerve fibers.

The brain is the centre of a wide system of communication. It has been found out that a constant flow of stimuli comes into the brain through the spinal cord. The stimuli come to the brain from our eyes, ears, and other sense organs for pain, temperature, smell and other feelings. When all the received stimuli have been summarized and analyzed the brain sends orders through the nerve fibers in the spinal cord to different parts of the human body. It is due to these orders that one eats, moves, hears, sees and does many other things.

To estimate the functions of different areas of the brain many experiments have been carried out by the investigators. It is due to such experiments that the investigators have been able to determine those areas of the brain which control vision, hearing, physical movements and even emotions. For example, it has been discovered that the part for thought, memory and feeling is found in the front of the cerebrum. The part for hearing is found at the side of the cerebrum and the part for vision is in the back of the cerebrum. The cerebellum is the centre which makes the muscles work as a team. The medulla is connected with such important acts as breathing and heartbeat.

Due to experimental studies it has been determined that the motor cortex controlling many body movements of the human being becomes tired rapidly. But the hypothalamus which controls such functions as blood pressure is almost never tired.

TASKS

I. Translate the following word combinations:

самый сложный механизм; черепная полость; два полушария; отдел спинного мозга; мозжечок; продолговатый мозг; передний мозг; большой мозг; толстый пучок нервных волокон; вес мозга; прямо и опосредованно; система связи; поток сигналов; глаза, уши и другие органы чувств; синтезировать и анализировать полученные сигналы; отправлять приказы; двигаться, слышать и видеть; определять функции различных областей мозга; управлять зрением и слухом; мышление, память и ощущения; дыхание и сердцебиение; двигательный отдел коры головного мозга; контролировать кровяное давление

II. Combine the part from A with the part from B to make up sentences:

A 1. The brain is … 2. The medulla is … 3. The nose is … 4. The cerebrum is … 5. The cerebellum is … 6. The motor cortex is … 7. The hypothalamus is … 8. The stimuli … 9. The tongue is …

B the organ of taste. the centre which makes the muscles work. the centre of wide system of communication. connected with breathing and heartbeat. come to the brain from our eyes, ears and other sense organs. the organ of smell. the part controlling body movements. the part controlling blood pressure. the part for thought, memory and feeling.

III. Find the odd word:

1. to investigate, to study, to receive, to determine

2. medulla, cerebrum, hypothalamus, cavity

3. pain, weight, length, width

4. vision, hearing, memory, smell

5. breathing, heartbeat, area, blood pressure

IY. Translate the following sentences:

1. Именно головной мозг является центром системы связи.

2. Именно мозг отправляет приказы по нервным волокнам к различным частям

тела.

3. Именно продолговатый мозг управляет такими функциями как дыхание и

сердцебиение.

4. Именно гипоталамус контролирует кровяное давление.

5. Именно мозжечок заставляет мышцы работать.

V. Express your agreement or disagreement with the following statements:

1. The most complicated mechanism which has ever been constructed is the heart.

2. The cranial cavity is the biggest cavity in the human body.

3. The brain is divided into three parts: the medulla, the forebrain and the cerebellum.

4. A constant flow of stimuli comes into the brain through the skin.

5. Eyes, ears, the tongue, the nose are the sense organs.

6. The tongue is the organ of smell.

7. The medulla makes the muscles work as a team.

8. The cerebrum is the part controlling vision and hearing.

9. Hypothalamus controlling blood pressure becomes tired very rapidly.

VI. Answer the following questions:

1. What is the brain?

2. Where is the brain located?

3. How many parts is the brain divided into? Name these parts.

4. What is the human brain weight?

5. How many cells does it consist of?

6. How are these cells connected to each other?

7. What sense organs can you name?

8. What do different parts of the brain (the medulla, the cerebrum, the cerebellum)

control?

9. What can you say about hypothalamus?

VI. Read the text B and answer the questions:

1. What two groups are reflexes divided into?

2. What is the difference between them?