SYSTEM EXAM
Actual Questions and Answers
Expert-Verified Explanation
This Exam contains:
✪ 40 Questions and Answers
✪ Multiple-choice and True/False Format
✪ Expert-Verified Explanations
✪ Verified with Trusted Textbooks
1. What is the primary function of the respiratory system?
A. To digest food
B. To provide structural support to the body
C. To provide efficient gas exchange and monitor blood pH
D. To transport nutrients to tissues
Answer: C
EXPLANATION: The respiratory system ensures oxygen enters the blood and carbon dioxide
is expelled, while also helping to maintain acid-base balance.
2. What is internal respiration?
A. The breathing process
B. Gas exchange at the alveolar level
C. Movement of air in and out of the lungs
D. Respiration at the molecular level
Answer: D
EXPLANATION: Internal respiration occurs at the cellular level, involving the exchange of
gases between blood and cells.
3. What is the approximate gas-holding capacity of human lungs?
A. 3L
B. 4L
C. 5L
D. 6L
Answer: D
EXPLANATION: Human lungs can hold approximately 6 liters of air, though the usable
volume is less due to residual volume.
, 4. What is the normal range for blood pH?
A. 6.8–7.2
B. 7.00–7.30
C. 7.35–7.45
D. 7.50–7.60
Answer: C
EXPLANATION: A normal blood pH range is slightly alkaline, between 7.35 and 7.45.
5. During inhalation, the diaphragm and intercostals ________ to ________ the chest
cavity.
A. Relax; contract
B. Contract; expand
C. Contract; shrink
D. Relax; expand
Answer: B
EXPLANATION: Contraction of the diaphragm and intercostal muscles increases thoracic
volume, allowing air in.
6. The atmospheric pressure at sea level is approximately:
A. 100 ATM
B. 500 ATM
C. 760 ATM
D. 1200 ATM
Answer: C
EXPLANATION: Standard atmospheric pressure is 760 mmHg or ATM at sea level.
7. Volume and pressure are:
A. Directly proportional
B. Inversely proportional
C. Unrelated
D. Equal in lungs
Answer: B
EXPLANATION: As per Boyle’s Law, when volume increases, pressure decreases, and vice
versa.
8. How much fluid is typically present in the pleural cavity?
A. 10 mL
B. 20 mL