Free Homeostasis MCQs with Answers

• A. A
• B. B
• C. C
• D. D

Explanation: Sparrows are endothermic, meaning they generate their own body heat and maintain a relatively constant internal body temperature…

• A. Convection
• B. Conduction
• C. Evaporation
• D. Radiation

Explanation: Vasodilation brings more blood and heat to the body surface, facilitating radiation and evaporative heat loss, which helps to cool the…

• A. Feather or fur
• B. Vasoconstriction
• C. Wind blowing across the body surface
• D. Counter current heat exchange

Explanation: Wind blowing across the body surface can increase the rate of heat exchange.

• A. A
• B. B
• C. C
• D. D

Explanation: When the outer air temperature is higher than body temperature, the body's thermoregulatory response shifts to cooling mechanisms such as…

• A. More sweating, vasoconstriction
• B. Less sweating, vasodilation
• C. Less sweating, vasoconstriction
• D. More sweating, vasodilation

Explanation: When the body is overheated, sweating and vasodilation are the primary mechanisms employed to regulate body temperature.

• A. Potassium excretion
• B. Sodium retention
• C. Water loss
• D. Urea excretion

Explanation: Aldosterone stimulates sodium reabsorption in DCT and collecting duct.

• A. Abdominal aorta (the large artery supplying blood to the body)
• B. Renal vein (carries oxygenated blood away from the kidney)
• C. Ureter (transports urine from kidney to urinary bladder)
• D. Inferior vena cava (large vein returning blood to the heart)

Explanation: A is the adrenal gland secreting adrenaline and noradrenaline for quick energy.

• A. Heterotherm
• B. Poikilotherm
• C. Ectotherm
• D. Endotherm

Explanation: A heterotherm is an organism that can regulate its body temperature, but not to a constant level.

• A. Higher ionic concentration inside vacuoles
• B. Higher osmotic pressure of the cell vacuole
• C. Large number of vacuoles in a plant cell
• D. Both a and b

Explanation: Option D is correct.Higher ionic concentration means water does not leave the vacuole, and the higher osmotic pressure of the vacuole…

• A. Aldosterone
• B. Thyroxine
• C. ADH
• D. Cortisone

Explanation: As a general principle, Sodium-Ion Concentration in the body is maintained by the hormone Aldosterone.

• A. The ascending limb of the loop of gentle
• B. The collecting duct
• C. The descending limb of the loop of gentle
• D. The proximal convoluted tubule

Explanation: ADH receptors are present on the collecting duct and thus ADH hormone acts on the collecting duct cells.

• A. I
• B. II
• C. III
• D. IV
• E. V

Explanation: Urinary bladder is the part of the urinary system that temporarily stores urine and releases it when filled.

• A. Glomerulus and Bowman's Capsule
• B. Proximal and distal end
• C. Ascending and descending arm
• D. Loop of henle

Explanation: The Glomerulus and Bowman's capsule are sited of filtration in the nephron while ascending/descending loop of Henle carries out…

• A. Renal pelvis
• B. Hilus
• C. Medulla
• D. Pyramid

Explanation: The medial concave border of a kidney contains a notch known as hilus through which the renal artery enters and the renal vein and ureter…

• A. Renin
• B. Atrial­ natriuretic factor
• C. Alcohol
• D. Caffeine

Explanation: Blood pressure regulation is the main function of renin. It works together with angiotensin and aldosterone to manage the levels of sodium…

• A. Urea in tadpole and ammonia in adult frog
• B. Ammonia in tadpole and urea in adult frog
• C. Urea in both tadpole and adult frog
• D. Urea in tadpole and uric acid in adult frog

Explanation: Ammonia is highly soluble in water, so in aquatic animals e.g., tadpole of frog, the nitrogenous waste products are excreted in the form…

• A. No Supply of Water
• B. Sufficient Supply of Water
• C. Excess Supply of Water
• D. Restriced Supply of Water

Explanation: When supply of water to the body is restricted the water inside the body is conserved to compensate it and vice versa.

• A. Homeothermic organisms
• B. Hyperthermic organisms
• C. Poikilothermic organisms
• D. None of these

Explanation: Homeothermic organisms are those which maintain their body tempareture when exposed to changing surrounding temperature.

• A. Sweat - Temperature regulation
• B. Saliva - Sense of food taste
• C. Sebum - Sexual attraction
• D. Humerus - Hindleg

Explanation: Sweat is secreted by sweat glands of skin and helps in regulating body temperature.

• A. When someone drinks a large amount of water, ADH release is suppressed.
• B. Exposure to cold temperatures stimulates ADH release.
• C. An increase in glomerular blood flow stimulates formation of angiotensin II.
• D. During summer when the body loses a lot of water due to evaporation, the release of ADH is suppressed.

Explanation: Antidiuretic hormone (ADH) or vasopressin increases the reabsorption of water in the distal convoluted tubule, collecting tubules and…