Task 1. Learn the following words and word combinations

amount	[ə'maunt]	количество
catalyst	['kæt(ə)lɪst]	катализатор
cell	[sel]	клетка
compound	['kɔmpaund]	смесь, соединение, составной
consume	[kən'sju:m]	потреблять
deficiency	[dɪ'fɪʃ(ə)nsɪ]	недостаток, недостаточность, дефицит
development	[dɪ'veləpmənt]	развитие
diverse	[daɪ'vɜːs]	разнообразный
enzyme	['enzaɪm]	фермент
essential	[ɪ'senʃ(ə)l]	существенный, важный, необходимый, основной
growth	[grəuθ]	рост
intestinal tract	[ɪn'testɪn(ə)l][trækt]	желудочно-кишечный тракт
multicellular	[mʌltɪsɛljʊlə]	многоклеточный
nutrient	['nju:trɪənt]	питательное вещество
obtain	[əb'teɪn]	получать
precursor	[prɪ'kɜːsə]	клетка- предшественник
prevent	[prɪ'vent]	предотвращать
quantity	['kwɔntətɪ]	количество
require	[rɪ'kwaɪə]	требовать (ч.-л)
scientist	['saɪəntɪst]	ученый
side-effect	[saɪd][ɪ'fekt]	побочное действие
tissue	['tɪʃu:]	ткань

Task 2.Find in the text the following words and word combinations, reproduce the context they are used in and translate it into Russian.

1. organic compound

2. tiny amounts

3. sufficient quantities

4. biological and chemical activity

5. biochemical functions

6. hormone-like functions

7. detachable molecules

8. best-known function

9. derive

10. shorten

11. water-soluble

12. fat-soluble

13. normal growth

14. periodically

15. differing schedules

Task 3.Answer the questions.

1. What is vitamin?

2. Can vitamins be synthesized in sufficient quantities by an organism?

3. Where are vitamins obtained from?

4. How many vitamins are universally recognized at present?

5. How are vitamins classified?

6. What biochemical functions of vitamins do you know?

7. What does the term vitamin mean?

8. Who is the author of this term?

9. How many fat-soluble and water-soluble vitamins are there in humans?

10. What are vitamins essential for?

11. How must humans consume vitamins to avoid deficiency?

12. What happens when vitamins are overdosed?