All Free Physiology MCQs with Answers

• A. IX
• B. VIII
• C. X
• D. XII

Explanation: Classical haemophilia, or haemophilia A, results from deficiency of factor VIII and produces a prolonged intrinsic-pathway clotting time.

• A. Heart rate
• B. Cardiac output
• C. Peripheral resistance
• D. All of the above

Explanation: Noradrenaline strongly stimulates alpha receptors, producing vasoconstriction and increased peripheral resistance.

• A. There is immediate increase in venous return
• B. Heart rate becomes stable at slightly more than normal
• C. Cerebral blood flow increase & becomes stable at more than normal
• D. Blood flow to the Apex of lung decrease

Explanation: Lying down removes the hydrostatic pooling of blood in the legs, so venous return rises immediately.

• A. Cerebral blood flow increases if there is increase in systolic blood pressure
• B. Body temperature increases
• C. Blood flow to muscle increases after 1½ minute
• D. Lymphatic flow from muscle decrease

Explanation: Exercise increases heat production, so body temperature rises. Cerebral blood flow is autoregulated rather than simply increasing with…

• A. decreases
• B. Increases
• C. Remains constant
• D. Increases then decreases

Explanation: During moderate exercise, cerebral autoregulation maintains cerebral blood flow approximately constant despite changes in systemic…

• A. Increase in heart rate
• B. Decreased vagal discharge
• C. Increased sympathetic discharge
• D. Decrease in blood pressure

Explanation: Baroreceptor stimulation increases vagal activity and inhibits sympathetic activity, reducing heart rate, contractility and vascular…

• A. Due to closure of semilunar valves
• B. Has longer duration than 1st heart sound
• C. Is occasionally split
• D. Marks the onset of diastole

Explanation: The second heart sound results from closure of the aortic and pulmonary valves, may be physiologically split, and marks the beginning of…

• A. Act as syncytium
• B. Has gap junctions
• C. Has multiple nuclei
• D. Has branching

Explanation: Cardiac muscle cells branch and connect through gap junctions, allowing the myocardium to function as a syncytium.

• A. AV Valve closes
• B. When ventricular pressure falls below aortic pressure
• C. None of the aboveConsult Online Doctors
• D. When ventricular pressure falls below atrial pressure

Explanation: Isovolumetric relaxation ends when ventricular pressure falls below atrial pressure, allowing the atrioventricular valves to open and…

• A. Purkinje system
• B. Bundle of HIS
• C. Right and left bundle branches
• D. AV nodeTry Prep Courses

Explanation: Purkinje fibres spread the impulse rapidly through the ventricular myocardium, activating ventricular muscle almost simultaneously.

• A. Arteries
• B. Capillaries
• C. Arterioles
• D. Venules

Explanation: Arterioles are the main resistance vessels, so their smooth-muscle tone controls tissue perfusion and the distribution of cardiac output.

• A. Chronotropic effect
• B. Dromotropic effect
• C. Bathmotropic
• D. Ionotropic effect

Explanation: The force of cardiac contraction is described by the inotropic effect, so the intended answer is option d, although it is misspelled as…

• A. Liver
• B. Brain
• C. Kidney
• D. Heart

Explanation: At rest, the liver receives the largest overall share of cardiac output when hepatic arterial and portal venous inflows are considered…

• A. 0.4 secondsExplore Anatomy Models
• B. 0.3 seconds
• C. 0.7 seconds
• D. 0.7 seconds

Explanation: At a heart rate of about 75 beats per minute, atrial systole lasts 0.1 seconds and ventricular systole 0.3 seconds, leaving about 0.4…

• A. 0.4 seconds
• B. 0.8 seconds
• C. 1.2 seconds
• D. 1.6 seconds

Explanation: A normal cardiac cycle lasts about 0.8 seconds at a heart rate of 75 beats per minute, calculated as 60 divided by 75.

• A. Sympathetic impulse
• B. Hormones
• C. Parasympathetic impulses
• D. Auto regulation

Explanation: Coronary blood flow is predominantly controlled by local metabolic autoregulation, particularly the effects of myocardial oxygen demand…

• A. Purkinje fibers
• B. SA node
• C. Bundle of His
• D. AV node

Explanation: Purkinje fibres conduct impulses fastest, allowing rapid activation of both ventricles and coordinated contraction.

• A. Isovolumetric contraction
• B. Isovolumetric relaxation
• C. Pre-diastole
• D. Pre-systole

Explanation: Aortic valve closure marks the start of isovolumetric ventricular relaxation, when all valves are briefly closed and ventricular pressure…

• A. cardiac output and body weight
• B. Stroke volume and pulse rateConsult Online Doctors
• C. Cardiac output and work of the heart
• D. Cardiac output and body surface area

Explanation: Cardiac index is cardiac output corrected for body surface area, expressed as litres per minute per square metre.

• A. Decreased B.P , decreased heart rate
• B. Increased blood pressure, increased heart rate
• C. Increased B.P, decreased heart rate
• D. Decreased B.P, increased heart rateTry Prep Courses

Explanation: Baroreceptor stimulation increases vagal activity and reduces sympathetic activity, slowing the heart and causing vasodilation.