The physiology of the lungs

The physiology of the lungs is associated with their structure. There are over 700,000,000 alveoli in the lungs. The total surface of the alveoli is about 90 sq.m (square metres). The lungs have many capillaries with the total surface of about 80 sq.m. This particular structure of the lungs enables the exchange of gases between the alveolar air and the blood.

Elastic fibers of connective tissue composing the walls of the alveoli, alveolar passages and the visceral pleura enable the lungs to dilate.

When one breathes normally not all the alveoli and capillaries of the lungs are opened. When respiration becomes deep, the number of the opened alveoli and capillaries increases. The flow of blood into the lungs increases when one breathes in and it decreases when one breathes out.

The regulation of the vital capacity of the lungs is of particular importance to the exchange of oxygen and carbon dioxide taking place in the lungs. It is considered that in the adult the vital capacity of the lungs is about 3-4 litres. When the depth of respiration increases the vital capacity may be 6 litres and even more.

The lungs take part in the production of physiologically active substances, in the regulation of blood coagulation, in the metabolism of proteins, fats and carbohydrates.

Exercise 5. Answer the questions:

1) What do the lungs contain?

2) What enables the exchange of gases between the alveolar air and the blood?

3) What enables the lungs to dilate?

4) What happens in the lungs when a person is breathing in?

5) What happens in the lungs when a person is breathing out?

6) What is the usual vital capacity of the lungs in the lungs?

7) What activities do the lungs take part in?

Exercise 6. Find English equivalents in the text:

Загальна поверхня, мати особливе значення, що відбувається у легенях, приймати участь у виробленні, обмін газів, сполучна тканина, життєва місткість, глибина дихання, коагуляція крові, обмін речовин, збільшуватися, зменшуватися, вважати.

Exercise 7. Find definitions to the following words:

Surface any of the many tiny air sacs of the lungs which allow for

rapid gaseous exchange

Respiration one of the pair organs, responsible for the process of respiration Coagulation the outside part or layer of smth

Alveolus the process of changing fluid into a solid or semi-solid state

Lung the process in living organisms of taking in oxygen from the

surroundings and giving out carbon dioxide

Exercise 8. Finish the sentences choosing the appropriate clause:

1) The patient stated that .... a) he had had pneumonia two years before. b) he has pneumonia.

2) The doctor thought that.... a) the white blood cell count-would be normal. b) the white blood cell count will be normal.

3) The physician said that .... a) the sanatorium treatment would help. b) the sanatorium treatment will help.

4) The scientists established that.... a) hemoglobin was the carrier of oxygen. , b) hemoglobin is the carrier of oxygen.

5) The nurse said that .... a) the doctor was making a morning round. b) the doctor is making a morning round.

6) The doctor told that... a) light diet would be very helpful. b) light diet will be very helpful.

Exercise 9. Make questions to the underlined phrases:

1) The right lung consists of three lobes.

2) New experimental findings were established by a young scientist.

3) My sister is suffering from pneumonia now.

4) The doctor has observed considerable changes in the lungs.

5) The nurse made an injection of antibiotics.

6) Students will be delivered a lecture in 2 days.

Регуляція життєвої ємкості легень

Метаболізм жирів та вуглеводів

Розширення та скорочення легень

Обмін кисню та вуглекислого газу

Загальна поверхня альвеол

• What is the structure of the lungs?

• What do the lungs take part in?

• Where are the lungs located?