Free Endocrine Physiology MCQs with Answers

• A. Increases intestinal absorption of calcium
• B. Bone resorption
• C. Bone deposition
• D. Decreases intestinal absorption of calcium

Explanation: Calcitonin lowers plasma calcium mainly by inhibiting osteoclast-mediated bone resorption, shifting the balance toward retention of…

• A. Vit - D & Calcium
• B. Parathormone
• C. Calcitonin
• D. All of the above

Explanation: Bone remodelling depends on vitamin D and calcium, while parathyroid hormone and calcitonin regulate calcium movement between bone, blood…

• A. Thyroxine
• B. ACTH
• C. Adrenaline
• D. Calcitonin

Explanation: Iodine is incorporated into tyrosine residues during synthesis of thyroid hormones, especially thyroxine (T4).

• A. Hyperparathyroidism
• B. Hypothyroidism
• C. Hypoparathyroidism
• D. Hyperthyroidism

Explanation: Hypoparathyroidism lowers parathyroid hormone and consequently reduces ionized calcium, producing neuromuscular irritability.

• A. Anterior pituitary
• B. Vasomotor center
• C. Juxtaglomerular apparatus
• D. Hypothalamus

Explanation: Vasopressin, or ADH, is synthesized by hypothalamic neurons and then transported to the posterior pituitary for storage and release.

• A. None of the above
• B. Parathyroids
• C. Pituitary
• D. Adrenal cortex

Explanation: A phaeochromocytoma arises from catecholamine-secreting chromaffin cells of the adrenal medulla.

• A. Hypothyroidism
• B. Tetany
• C. Paget's disease of the bone
• D. Osteogenesis imperfecta

Explanation: Low ionized calcium increases neuronal and muscular excitability, producing tetany with spasms and signs such as Trousseau and Chvostek…

• A. ACTH
• B. Luetinizing hormone
• C. Growth hormone
• D. Antidiuretic hormone

Explanation: Antidiuretic hormone is synthesized in the hypothalamus and released from the posterior pituitary.

• A. Hypoglycemia
• B. Psychosis
• C. Peptic ulcers
• D. Osteoporosis

Explanation: Long-term corticosteroid excess commonly causes hyperglycaemia, psychosis, peptic ulcer risk and osteoporosis, so hypoglycaemia is the…

• A. Cortisol
• B. Progesterone
• C. Testosterone
• D. Corticosterone

Explanation: Progesterone is an intermediate in the steroidogenic pathways leading to both adrenal cortical hormones and gonadal steroids.

• A. Acute Pancreatitis
• B. Carcinoma of Head of Pancreas
• C. Endocrine Dysfunction of Pancreas
• D. Acinar Function of the Pancreas

Explanation: The glucose tolerance test evaluates how effectively insulin and the endocrine pancreas handle a glucose load.

• A. HMG. CoA reductase
• B. HMG- CoA lyase
• C. HMG- CoA synthase
• D. Thiolase

Explanation: Insulin promotes cholesterol synthesis by activating HMG-CoA reductase, the rate-limiting enzyme of cholesterol production.

• A. Clonidine
• B. Amiodarone
• C. Hydralazine
• D. Penicillamine

Explanation: Amiodarone contains a large iodine load and can disturb thyroid hormone synthesis or release, producing either hyperthyroidism or…

• A. Decline plasma calcium level
• B. Neuromuscular hyperexcitability
• C. Decrease in plasma phosphate level
• D. hypo calcemic tetany

Explanation: Loss of parathyroid hormone lowers plasma calcium and raises phosphate because renal phosphate excretion falls.

• A. Plasma K+
• B. pH of the plasma
• C. Plasma Na+
• D. Angiotensin II level

Explanation: A fall in plasma sodium reduces effective circulating volume and activates renin, angiotensin II and aldosterone secretion to promote…

• A. Hypertonicity of muscles
• B. Hypotonicity of muscles
• C. Increased serum calcium concentration
• D. None of the above

Explanation: Tetany commonly results from hypocalcaemia, which causes repetitive nerve firing and sustained muscle spasms, producing hypertonicity.

• A. Relaxation of muscle
• B. Excitability of the muscle
• C. Increase the renal absorption
• D. Depression of Nervous system

Explanation: A fall in serum calcium lowers the threshold for nerve and muscle excitation, causing tingling, spasms and increased muscle excitability.

• A. Pot- belly
• B. Idiotic look
• C. Normal intelligence
• D. Stunted growth

Explanation: Childhood hypothyroidism causes cretinism with stunted growth, a pot belly and impaired intellectual development.

• A. Adrenalin
• B. Growth Hormone
• C. Insulin
• D. Thyroxine

Explanation: Thyroxine is lipid-soluble and acts through intracellular nuclear receptors that regulate gene transcription.

• A. Parathyroid hormone
• B. Calcitonin
• C. 1,25 dihydroxycholecalciferols
• D. Tumor necrosis factor

Explanation: Calcitonin directly inhibits osteoclast activity and therefore reduces bone resorption.