Read the text. Find out key sentences and summarize the text



 

 

 

Effects of anabolic steroids (hormones)

 

There are not to be confused with the various corticosteroid drugs often prescribed by doctors for conditions such as rheumatoid arthritis and Crohn's disease. Anabolic steroids have only a very limited use in ordinary medicine, such as building up muscle in a patient who has been bedridden for some time.

They are misused by some athletes and body builders in order to increase muscle size and strength. Because they are derived from the male hormone testosterone, they may also have the effect of stimulating aggression. Some athletes claim the drugs help them train harder and recover more quickly from injury.

Their use is prohibited by sporting bodies and athletes found using steroids are liable to be disqualified and banned from competition.

There are many potential problems associated with these drugs:

· often steroids are injected using shared equipment, with the attendant risks of HIV and other infections;

· in young people, steroids can restrict growth;

· in men, they have side-effects on the reproductive system, such as reduced sex drive and lowered sperm count;

· in women, 'masculine' side-effects such as deeper voice and smaller breasts may be permanent even when the drug use has stopped;

· they can cause liver damage leading to jaundice or cancer of the liver.

These drugs circulate in some public gyms and health clubs. It is illegal to supply them without a prescription, but not illegal to possess them.

                                 

UNIT-2. THE MICROUNIVERSE

Read the text and answer the questions.

BIOLOGY OF THE CELL

You and all other organisms are made up of cells. Cells are the building blocks of organisms. They form the parts of organisms and carry out all of an organism's processes and functions. They are very complex structures which are also called the micro-universe. Because of its small size, however, the cell's structure has not yet been fully understood. Scientists are still carrying out research on cellular systems. Our bodies are composed of trillions of cells. Every adult human body contains about 100 trillion cells. But these cells are very small. When a million of our body cells are gathered together, they occupy a space no bigger than a pinpoint.

There are 200 different types of cells in our bodies. In fact, all of these cells are composed of identical components, yet each performs a different task. For example muscle cells in your legs enable you to walk and run. Your blood cells transport oxygen to your body cells. Skin cells, on the other hand, are clumped together and closely arranged in a line. So your skin is a barrier to microbes and water.

When you describe the structure of an object, you describe what it is made of and how its parts are put together. According to their structure, cells are divided two types: prokaryotic cells and eukaryotic cells.

Procaryotic cells: pro- means before; karyo-means nucleus. Prokaryotic cells do not have a nucleus or membrane-bound organelles such as vacuoles, mito- chondria, or lysosomes. Bacteria are prokaryotic cells.

Eukaryotic cell: eu-means true; karyo-means nucleus. This cell type has a true us. All organisms except bacteria have eukaryotic cells.

 

 

                  

Cell membrane
Food Vacuole

 

Exercises

 

Answer the questions.

1. What are cells?

2. How many cells does every adult body contain?

3. How many types of cells are there in our body?

4. Why has not the cell’s structure yet been fully understood?

5. What cells enable us walk and run?

6. What is the function of the blood cells?

7. What is our skin a barrier to?

8. How many types are the cells divided into according to their structure?

9. What is the difference between prokaryotic and eukariyotic cells?

10. Do all organisms have eukaryotic cells?

 

 


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