The Exchange of Gases in the Lungs
The exchange of gases takes place in the alveoli of the lungs. Oxygen passes into the blood and carbon dioxide passes into the atmospheric air.
The exchange of oxygen and carbon dioxide is due to the difference of partial (парциальное) pressure of these gases in the alveolar air and in the venous blood.
The partial pressure of oxygen in the alveolar air is higher than in the venous blood. The transfer of oxygen from the atmospheric air into the blood is due to this difference of pressures.
The partial pressure of carbon dioxide is higher in the venous blood and this enables carbon dioxide to pass from the blood into alveolar air.
The process of transfer of gases into the medium (среда) with a lower partial pressure iscalled diffusion. Hemoglobin is that substance of the blood which transfers oxygen in the blood. The oxygen capacity of the blood averages to 18-20 milliliters (ml) per 100 gr of blood. Carbon dioxide is transferred in combination with hemoglobin and as bicarbonic salts.
The combination of oxygen and hemoglobin is called oxyhemoglobin, that of carbon dioxide and hemoglobin — carbohemoglobin.
Task 1.
Answer the questions:
1. Where does the exchange of gases take place?
2. Where do oxygen and carbon dioxide pass into?
3. Where the partial pressure of oxygen is higher?
4. What is called Diffusion?
5. What is hemoglobin?
6. What is the oxygen capacity of the blood?
7. How is carbonic dioxide transferred?
8. What is called oxyhemoglobin?
9. What is carbohemoglobin?
Task 2.
Complete the sentences. Put the verbs in proper form:
1. On physical exertion the patient’s … become deep.
2. When the temperature is high a patient usually … deeply.
3. When one … the lungs dilate.
4. When one … the lungs contract.
(Breathe, breathe out, breath, breathe in)
1. a helicopter, a plane, a star, the sun, the moon, clouds, a rainbow.
2. water, a boat, a fish, a duck, a fisherman, a yaht, sand, a rock, a beach.
3. water, a ship,a lighthouse, a seaside, seagulls, waves, swimmers, dolphins, jelly fish.
4. a table cloth, food, a plate, a knife, a spoon, a fork, a cup.
5. benches, trees, flowers, roads, people, dogs, attractions.
6. a table, some chairs, a sofa, a carpet, a TV, pot-flowers, pictures.
7. a pen, a pencil, a table lamp, а computer, a printer, а воок.
8. a microwave, a gas cooker, a fridge, a dishwasher, a table and some stools (chairs).
9. a cow, a horse, sheep, a pig, a goat, geese, ducks, hens and chicks, cocks.
2. He turned on the radio. Played Brahms piano Concerto. -
3. He sat with his head bowed on his knees. -
4. Are you interested in the picture that you were offered? -
5. She felt that from her hiding something. -
6. Have you ever been taught how to behave? -
7. He had to have surgery. -
8. They say it can't be seen for 6 weeks. -
9. I stole a stamp collection. -
10. He was given a first class education. -
11. Look! Someone spilled coffee on the tablecloth. -
12. The need to make lessons more interesting. -
13. Need to do something for these people. -
14. Basketball is played all over the world. -
15. I'm afraid that this picture cannot be restored. -
16. On the day of birth gave her a box of chocolates. -
17. His friend highly recommended. -
18. With me so never spoke. -
19. For every penny required to report. -