Physiology MCQs
Physiology MCQs help medical and dental students develop a thorough understanding of the body's functional mechanisms. These multiple-choice questions focus on various systems such as cardiovascular, respiratory, renal, digestive, endocrine, and neurophysiology. Practicing these MCQs enhances knowledge retention and exam performance in tests like MDCAT, NTS, USMLE, and FCPS. Whether you're preparing for academic exams or professional licensure, these quizzes provide a solid framework for mastering the dynamic processes of the human body.
Q: Blood glucose is maintained during fasting primarily through
A) Lipogenesis
B) Glycogenesis
C) Gluconeogenesis
D) Glycolysis
✅ Correct Answer: C
Explanation: The liver converts non-carbohydrate precursors into glucose during fasting states.
Q: Cardiac muscle cells are connected by structures known as
A) Sarcomeres
B) Intercalated discs
C) Nodes of Ranvier
D) Axons
✅ Correct Answer: B
Explanation: Intercalated discs allow rapid impulse transmission and synchronized contraction of cardiac muscle.
Q: The enzyme responsible for breaking down acetylcholine is
A) Peptidase
B) Lipase
C) Amylase
D) Acetylcholinesterase
✅ Correct Answer: D
Explanation: Acetylcholinesterase quickly degrades acetylcholine to terminate nerve signal transmission.
Q: Glomerular filtration is driven mainly by
A) Enzymatic action
B) Osmotic pressure
C) Nerve signals
D) Blood pressure
✅ Correct Answer: D
Explanation: Hydrostatic pressure in the glomerular capillaries forces plasma into Bowman's capsule.
Q: The pacemaker of the heart is known as the
A) Atrioventricular node
B) Bundle of His
C) Purkinje fibers
D) Sinoatrial node
✅ Correct Answer: D
Explanation: The SA node initiates each heartbeat and sets the heart rate.
Q: Hormone that stimulates red blood cell production is
A) Cortisol
B) Estrogen
C) Erythropoietin
D) Glucagon
✅ Correct Answer: C
Explanation: Erythropoietin, secreted by the kidneys, promotes erythropoiesis in the bone marrow.
Q: The stretch reflex helps maintain
A) Body temperature
B) Muscle tone
C) Blood sugar
D) Pulse rate
✅ Correct Answer: B
Explanation: It provides automatic correction to muscle length, maintaining posture and balance.
Q: The most abundant gas in exhaled air is
A) Argon
B) Carbon dioxide
C) Oxygen
D) Nitrogen
✅ Correct Answer: D
Explanation: Nitrogen is inert and constitutes the majority of both inhaled and exhaled air.
Q: During strenuous exercise, muscles shift to anaerobic respiration leading to accumulation of
A) Ammonia
B) Lactic acid
C) Urea
D) Glycogen
✅ Correct Answer: B
Explanation: Anaerobic glycolysis results in lactic acid buildup, causing fatigue.
Q: Bicarbonate ions primarily function as a
A) Enzyme
B) Hormone
C) Buffer
D) Lipid
✅ Correct Answer: C
Explanation: Bicarbonate maintains blood pH by neutralizing excess acids or bases.