The muscular sheet which divides the body cavity into thorax and abdomen is termed as :

1. Inner pleura
2. Rib cage
3. Outer pleura
4. Diaphragm

The basic structural and functional unit of the lungs is :

1. Pleura
2. Alveolus
3. Capillary
4. Diaphragm

The diagram given alongside is an experimental set up mimicking a certain process occurring in living beings. Study the figure and answer the following questions :

(i) Name the process and define it.

(ii) What are the two phases of the above mentioned process shown as (A) and (B) ?

(iii) Name the particular organs of the body shown in the figure with :
(a) Bell jar (b) Balloons (c) Rubber sheet

(iv) How do these phases (A) and (B) differ with respect to the position of ribs ?

(v) Does the breathing rate of a young boy and an old person differ ? Explain.

Correct the following statements by changing the first/ last word only :

1. BCG is a kind of vaccine used to prevent Pneumonia.
2. Streptomycin is a kind of vaccine.
3. Breathing is a bio-chemical process.
4. The amount of oxygen in expired air is 21%.
5. The front opening of the trachea is guarded by a muscular flap called diaphragm.