Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. The main function of the respiratory system is:
A. Digesting food
B. Transporting nutrients
C. Gas exchange
D. Producing hormones
Correct Answer: C
Rationale: The respiratory system facilitates oxygen intake and
carbon dioxide elimination.
2. Oxygen is primarily transported in the blood:
A. Dissolved in plasma
B. Bound to hemoglobin
C. Bound to platelets
D. Bound to plasma proteins
Correct Answer: B
Rationale: Hemoglobin carries most oxygen, ensuring efficient
delivery to tissues.
,3. Carbon dioxide is carried in blood mainly as:
A. Dissolved CO₂
B. Carbaminohemoglobin and bicarbonate
C. Bound to hemoglobin only
D. Bound to plasma proteins only
Correct Answer: B
Rationale: CO₂ reacts with water to form bicarbonate, facilitating
transport.
4. The trachea is reinforced by:
A. Smooth muscle
B. Hyaline cartilage rings
C. Elastic fibers
D. Bone
Correct Answer: B
Rationale: Cartilage keeps the airway open for unobstructed
airflow.
5. The primary inspiratory muscle is:
A. Diaphragm
B. External intercostals
C. Internal intercostals
D. Abdominals
Correct Answer: A
,Rationale: Diaphragm contraction increases thoracic volume for
inhalation.
6. External intercostals assist by:
A. Elevating ribs during inspiration
B. Compressing the abdomen
C. Expelling air forcefully
D. Producing surfactant
Correct Answer: A
Rationale: They increase thoracic cavity volume during normal
breathing.
7. Pulmonary surfactant is produced by:
A. Type I alveolar cells
B. Type II alveolar cells
C. Macrophages
D. Bronchiolar epithelium
Correct Answer: B
Rationale: Surfactant reduces alveolar surface tension and prevents
collapse.
8. Tidal volume refers to:
A. Air inhaled or exhaled during normal breathing
B. Maximum inhalation
C. Residual volume
, D. Dead space
Correct Answer: A
Rationale: It represents the volume of air exchanged in a single
normal breath.
9. Inspiratory reserve volume (IRV) is:
A. Air inhaled beyond tidal inspiration
B. Air exhaled normally
C. Residual air
D. Total lung capacity
Correct Answer: A
Rationale: IRV allows deep breaths beyond the resting tidal volume.
10. Expiratory reserve volume (ERV) is:
A. Air exhaled beyond normal tidal exhalation
B. Tidal volume
C. Residual volume
D. Total lung capacity
Correct Answer: A
Rationale: Used during forced exhalation to increase air expulsion.
11. Residual volume is:
A. Air remaining in lungs after maximal exhalation
B. Tidal volume
C. Inspiratory reserve only