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Texts: the digestive system. Nutrition. Pre-reading and reading tasks

  1. Study the vocabulary which is intended to aid your comprehension of the text:

break up (v)

['breIk'Ap]

разбивать

chew (v)

[tSu:]

жевать

expel

[Ik'spel]

удалять

repair (v)

[rI'peq]

восстанавливать

secrete (v)

[sI'kri:t]

выделять

swallow (v)

['swPlqV]

глотать

bump

[bAmp]

выпуклость

chyme

[kaIm]

пищевая кащица

coiled-up tubing

['kOIld 'Ap 'tju:bIN]

свернутые трубки

esophagus (pl. esophagi)

[I'sPfqgqs] [I'sPfqgaI]

пищевод

fundus

['fAndqs]

дно

lining

['laInIN]

выстилка

pancreas

['pxNkrIqs]

поджелудочная железа

sac

[sxk]

мешочек

stomach

['stAmqk]

желудок

villi

['vIlaI]

ворсинки

crescent

['kres(q)nt]

серповидный

esophageal

[I"sPfq'dZi:ql]

относящийся к пищеводу

gastric

['gxstrIk]

желудочный

longitudinal

["lPndZI'tju:d(q)nql]

продольный

oblique

[q'bli:k]

наклонный, косой

pyloric

[paI'lPrIk]

пилорический

tubular

['tju:bjVlq]

трубчатый

2. Make sure you know the meaning of these words and word combinations:

carbohydrates

bloodstream

enzyme

circular

gastric juice

contraction of muscles

rectum

sphincter

hydrochloric acid

carbohydrates

finger-like

3. Read the text carefully to fulfil the tasks that follow. The digestive system

We need food in order to live; it is the fuel for our body’s energy and growth. There are three main kinds of food: protein (found in meat, cheese, and nuts, for example), carbohydrates (found in bread and potatoes), and fat (found in oils and butter). Proteins are used for repairing the body and for growing; carbohydrates and fats are needed for providing energy.

Digestion is a process that begins when we put food in our mouths and ends when the food has been absorbed into the bloodstream. It takes up to eighteen hours for digestion to occur. This is not surprising because our food has to travel through more than 26 feet of coiled-up tubing called the small intestine. On its journey food gets broken down by acid and enzymes. An enzyme is a chemical that changes food into a substance we can easily absorb.

When we chew, our teeth break up food into small pieces for swallowing. Food then travels down a muscular tube called the esophagus, to the stomach. The stomach is a thick muscular sac positioned on the left side of the body just beneath the ribs. The upper region of the stomach, closest to the heart, is called the cardiac region. Below that is the crescent part of the sac called the fundus. The pyloric region is tubular and connects the stomach to the small intestines. The wall of the stomach is made up of three thick layers of muscle. One layer is composed of longitudinal, one of circular, and the other of oblique (diagonal) fibers. The powerful contractions of these muscles break up the food, mix it with gastric juice, and move it down the tract. Gastric juice is a mixture of hydrochloric acid and enzymes that further digest the food. Gastric juice and mucus are secreted by the small gastric glands in the lining of the stomach. The mucus helps protect the stomach from its own digestive enzymes and acid. The partially digested food, called chyme, is pushed through the pyloric sphincter into the small intestine. The pyloric sphincter is similar in structure and function to the lower esophageal sphincter.

In the small intestine food is broken up into useful substances and waste substances by enzymes, which are produced by a gland called the pancreas. Inside the small intestine finger-like bumps, known as villi, contain blood vessels that absorb the useful substances into the bloodstream. Waste substances remain and pass into the large intestine, where water is absorbed until the waste becomes solid. This waste is later expelled from the rectum.