Question

Q.5. Given alongside is the figure of human lung. Guidelines for 1 to 4 parts are indicated below:
(1) Air rich in CO 2 ;
(2) Vertebra;
(3) Muscles of relaxed diaphragm; (4) Depressed ribs. (i) Which state of breathing is represented in the figure? (ii) What is dead airspace? (iii) Name the muscles which relax in this process. (iv) What is the composition of CO2 in expired air?​

Answer 1

.5. Given alongside is the figure of human lung. Guidelines for 1 to 4 parts are indicated below:

(1) Air rich in CO 2 ;

(2) Vertebra;

(3) Muscles of relaxed diaphragm; (4) Depressed ribs. (i) Which state of breathing is represented in the figure? (ii) What is dead airspace? (iii) Name the muscles which relax in this process. (iv) What is the composition of CO2 in expired air?

Answer 2

Answer:

The action of breathing in and out is due to changes of pressure within the thorax, in comparison with the outside. This action is also known as external respiration. When we inhale the intercostal muscles (between the ribs) and diaphragm contract to expand the chest cavity. The diaphragm flattens and moves downwards and the intercostal muscles move the rib cage upwards and out.

2. an unventilated air space in which the air does not circulate.

3.Relaxed normal expiration is a passive process, happens because of the elastic recoil of the lungs and surface tension. However there are a few muscles that help in forceful expiration and include the internal intercostals, intercostalis intimi, subcostals and the abdominal muscles.

4.Gas % in inhaled air % in exhaled air

Carbon dioxide 0.04 4

Nitrogen 79 79