Physiology MCQs
Physiology MCQs help medical and dental students master body functions across cardiovascular, respiratory, renal, digestive, endocrine, and neurophysiology systems. Ideal for MDCAT, NTS, USMLE, and FCPS, these quizzes boost retention and exam success.
Q: The volume of air remaining in lungs after maximal expiration
A) Tidal volume
B) Inspiratory reserve
C) Residual volume
D) Vital capacity
✅ Correct Answer: C
Explanation: Residual volume cannot be exhaled and keeps alveoli from collapsing.
Q: Thyroid hormones primarily affect
A) Growth and metabolism
B) Immune function
C) Vision and hearing
D) Blood clotting
✅ Correct Answer: A
Explanation: T3 and T4 regulate basal metabolic rate and promote development and growth.
Q: The part of the nephron responsible for bulk reabsorption
A) Distal tubule
B) Proximal tubule
C) Loop of Henle
D) Collecting duct
✅ Correct Answer: B
Explanation: Proximal tubule reabsorbs about 65% of filtered sodium and water.
Q: Cerebrospinal fluid is produced by
A) Pituitary gland
B) Arachnoid granulations
C) Cerebral cortex
D) Choroid plexus
✅ Correct Answer: D
Explanation: The choroid plexus in ventricles secretes cerebrospinal fluid.
Q: The hormone regulating circadian rhythm
A) Insulin
B) Estrogen
C) Melatonin
D) Cortisol
✅ Correct Answer: C
Explanation: Melatonin, secreted by the pineal gland, helps synchronize sleep-wake cycles.