Respiration Mcqs Breathing And The Exchange Of Gases

Here Are 50 Multiple-Choice Questions (Mcqs) Related To

BREATHING AND THE EXCHANGE OF GASES


1. Which of the following is not a function of the respiratory system?

a) Gas exchange

b) Regulation of blood pH

c) Digestion

d) Vocalization

**Answer: c) Digestion**



2. The process of breathing in is also known as:

a) Expiration

b) Inhalation

c) Exhalation

d) Respiration

**Answer: b) Inhalation**



3. During inhalation, the diaphragm:

a) Contracts and moves upwards

b) Contracts and moves downwards

c) Relaxes and moves upwards

d) Relaxes and moves downwards

, **Answer: b) Contracts and moves downwards**



4. Which gas is most abundant in the air we breathe?

a) Oxygen (O2)

b) Carbon dioxide (CO2)

c) Nitrogen (N2)

d) Hydrogen (H2)

**Answer: c) Nitrogen (N2)**



5. Where does the primary exchange of gases occur in the respiratory system?

a) Trachea

b) Bronchi

c) Alveoli

d) Pharynx

**Answer: c) Alveoli**



6. The enzyme present in the saliva and respiratory tract that destroys harmful
microorganisms is:

a) Pepsin

b) Amylase

c) Lipase

d) Lysozyme

, **Answer: d) Lysozyme**



7. Which part of the brain controls the basic rhythm of breathing?

a) Cerebellum

b) Medulla oblongata

c) Hypothalamus

d) Cerebral cortex

**Answer: b) Medulla oblongata**



8. The partial pressure of oxygen is highest in which part of the respiratory
system?

a) Trachea

b) Bronchi

c) Alveoli

d) Pharynx

**Answer: c) Alveoli**



9. The diffusion of gases in the lungs and body tissues occurs due to differences in:

a) Pressure

b) Temperature

c) Humidity

d) Density