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: The reflex that prevents overinflation of the lungs
A) Hering–Breuer reflex
B) Withdrawal reflex
C) Babinski reflex
D) Moro reflex
✅ Correct Answer: A
Explanation: The Hering–Breuer reflex inhibits inspiration when lungs are overstretched.
Q: Vasodilation in exercising muscles is caused by
A) Accumulation of metabolites
B) Increased sympathetic tone
C) Increased oxygen
D) Decreased lactic acid
✅ Correct Answer: A
Explanation: Metabolites like CO₂ and adenosine promote local vasodilation.
Q: Sperm maturation primarily occurs in the
A) Vas deferens
B) Epididymis
C) Prostate
D) Seminal vesicle
✅ Correct Answer: B
Explanation: Sperm gain motility and are stored in the epididymis before ejaculation.
Q: The major site of hematopoiesis in adults
A) Kidney
B) Bone marrow
C) Liver
D) Spleen
✅ Correct Answer: B
Explanation: Red bone marrow continuously produces blood cells throughout life.
Q: Primary taste sensed at the back of the tongue
A) Sweet
B) Bitter
C) Sour
D) Salty
✅ Correct Answer: B
Explanation: Bitter taste is primarily detected by receptors at the back of the tongue.
Q: The organ with the largest blood flow per gram of tissue
A) Heart
B) Brain
C) Kidney
D) Liver
✅ Correct Answer: C
Explanation: Kidneys receive a high proportion of cardiac output relative to their size.
Q: Cortisol release follows
A) Sleep-wake rhythm
B) Insulin release
C) Light exposure
D) Fasting state
✅ Correct Answer: A
Explanation: Cortisol secretion peaks in the early morning and follows a circadian pattern.
Q: The neurotransmitter at the neuromuscular junction
A) Dopamine
B) Norepinephrine
C) Serotonin
D) Acetylcholine
✅ Correct Answer: D
Explanation: Acetylcholine binds to nicotinic receptors on skeletal muscle, causing contraction.
Q: The reflex arc component that carries impulses to the CNS
A) Motor neuron
B) Effector
C) Receptor
D) Sensory neuron
✅ Correct Answer: D
Explanation: Sensory neurons transmit stimuli from receptors to the spinal cord or brain.
Q: The spinal tract responsible for pain and temperature
A) Spinothalamic
B) Reticulospinal
C) Vestibulospinal
D) Corticospinal
✅ Correct Answer: A
Explanation: The spinothalamic tract carries sensory input for pain and thermal sensations.