Question

(a) Fig. 1.1 is a diagram of the gas exchange system.

(i) Identify the parts labelled A and B in Fig. 1.1.
A ……………………………………………………………………………………………………………………….
B ……………………………………………………………………………………………………………………….
(ii) Alveoli are the gas exchange surface in humans.
State two features of an efficient gas exchange surface.
1 ……………………………………………………………………………………………………………………….
2 ……………………………………………………………………………………………………………………….
(iii) State the name of the cells in the gas exchange system that produce mucus.
………………………………………………………………………………………………………………………….

(b) A student measures their breathing rate at rest and during exercise.
Table 1.1 shows the results.

(i) Calculate the difference in breathing rate between rest and during exercise in Table 1.1.

difference in breathing rate = …………………….. breaths per minute 
(ii) Tick (√) two boxes to explain the difference in breathing rate during exercise shown in Table 1.1.
There is a decrease in production of water vapour.                                                                             
There is a decrease in the use of oxygen by muscles.                                           
There is an increase in carbon dioxide concentration in the blood.                   
There is an increase in the rate of aerobic respiration.                                         
There is an increase in water intake.