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: Conduction velocity is fastest in
A) Thin myelinated fibers
B) Unmyelinated fibers
C) Large myelinated fibers
D) C fibers
✅ Correct Answer: C
Explanation: Large myelinated fibers conduct impulses more rapidly due to saltatory conduction.
Q: The primary buffer system in the extracellular fluid
A) Bicarbonate buffer
B) Phosphate buffer
C) Protein buffer
D) Hemoglobin buffer
✅ Correct Answer: A
Explanation: The bicarbonate buffer system maintains pH in blood and extracellular fluids.
Q: Increased carbon dioxide levels in blood stimulate
A) Decreased ventilation
B) Metabolic alkalosis
C) Increased ventilation
D) Vasoconstriction
✅ Correct Answer: C
Explanation: Elevated CO₂ levels trigger medullary centers to increase respiratory rate.
Q: The hormone that increases renal water reabsorption
A) Oxytocin
B) Cortisol
C) Antidiuretic hormone
D) Epinephrine
✅ Correct Answer: C
Explanation: ADH increases water permeability in the kidney collecting ducts.
Q: The stimulus for erythropoietin release
A) Acidosis
B) Hyperglycemia
C) Hypoxia
D) Dehydration
✅ Correct Answer: C
Explanation: Erythropoietin is secreted in response to low oxygen to stimulate red blood cell production.