Q.1 Which gland is known as the 'master gland' of the endocrine system?
Thyroid gland
Pituitary gland
Adrenal gland
Pineal gland
Explanation - The pituitary gland is called the master gland because it secretes hormones that regulate other endocrine glands.
Correct answer is: Pituitary gland
Q.2 Which hormone regulates blood glucose by lowering its concentration?
Glucagon
Insulin
Cortisol
Adrenaline
Explanation - Insulin decreases blood glucose by promoting glucose uptake into cells and stimulating glycogen synthesis.
Correct answer is: Insulin
Q.3 Where is the hormone melatonin primarily produced?
Pituitary gland
Pineal gland
Hypothalamus
Adrenal gland
Explanation - Melatonin is secreted by the pineal gland and helps regulate circadian rhythms.
Correct answer is: Pineal gland
Q.4 Which part of the adrenal gland secretes catecholamines such as adrenaline?
Adrenal cortex
Adrenal medulla
Zona glomerulosa
Zona fasciculata
Explanation - The adrenal medulla produces adrenaline and noradrenaline, crucial for the fight-or-flight response.
Correct answer is: Adrenal medulla
Q.5 Thyroxine (T4) and triiodothyronine (T3) are secreted by which gland?
Adrenal gland
Pituitary gland
Thyroid gland
Parathyroid gland
Explanation - The thyroid gland secretes T3 and T4, which regulate basal metabolic rate and growth.
Correct answer is: Thyroid gland
Q.6 Which hormone is secreted by the posterior pituitary gland?
Growth hormone
Oxytocin
Prolactin
TSH
Explanation - The posterior pituitary stores and releases oxytocin and ADH, though they are synthesized in the hypothalamus.
Correct answer is: Oxytocin
Q.7 Parathyroid hormone (PTH) increases blood levels of which ion?
Sodium
Calcium
Potassium
Magnesium
Explanation - PTH raises blood calcium levels by increasing bone resorption, renal calcium reabsorption, and vitamin D activation.
Correct answer is: Calcium
Q.8 Which hypothalamic hormone stimulates release of ACTH from the anterior pituitary?
CRH
TRH
GnRH
GHRH
Explanation - Corticotropin-releasing hormone (CRH) stimulates secretion of adrenocorticotropic hormone (ACTH).
Correct answer is: CRH
Q.9 Which pancreatic cells secrete glucagon?
Beta cells
Alpha cells
Delta cells
F cells
Explanation - Alpha cells in the islets of Langerhans secrete glucagon, which increases blood glucose.
Correct answer is: Alpha cells
Q.10 Which hormone is responsible for stimulating milk production?
Oxytocin
Prolactin
Estrogen
Progesterone
Explanation - Prolactin from the anterior pituitary stimulates milk synthesis in mammary glands.
Correct answer is: Prolactin
Q.11 Which endocrine gland regulates basal metabolic rate?
Adrenal gland
Thyroid gland
Pancreas
Pituitary gland
Explanation - Thyroid hormones regulate metabolism, growth, and development.
Correct answer is: Thyroid gland
Q.12 Which hormone promotes water reabsorption in the kidneys?
ADH
Aldosterone
Cortisol
PTH
Explanation - Antidiuretic hormone increases water reabsorption in the collecting ducts of the kidney.
Correct answer is: ADH
Q.13 Which hormone stimulates uterine contractions during labor?
Estrogen
Progesterone
Oxytocin
Relaxin
Explanation - Oxytocin promotes strong uterine contractions during childbirth.
Correct answer is: Oxytocin
Q.14 Which adrenal cortex zone produces mineralocorticoids like aldosterone?
Zona glomerulosa
Zona fasciculata
Zona reticularis
Medulla
Explanation - The zona glomerulosa produces aldosterone, which regulates sodium and potassium balance.
Correct answer is: Zona glomerulosa
Q.15 Which hormone regulates circadian rhythm?
Cortisol
Insulin
Melatonin
Thyroxine
Explanation - Melatonin, secreted by the pineal gland, regulates sleep-wake cycles.
Correct answer is: Melatonin
Q.16 Which hormone stimulates red blood cell production?
Erythropoietin
Prolactin
Cortisol
TSH
Explanation - Erythropoietin, produced by the kidneys, stimulates bone marrow to produce red blood cells.
Correct answer is: Erythropoietin
Q.17 Which pancreatic hormone inhibits both insulin and glucagon release?
Amylin
Somatostatin
C-peptide
Pancreatic polypeptide
Explanation - Somatostatin from delta cells inhibits both insulin and glucagon secretion.
Correct answer is: Somatostatin
Q.18 Which hormone is essential for female ovulation?
FSH
LH
Prolactin
Progesterone
Explanation - The LH surge triggers ovulation and corpus luteum formation.
Correct answer is: LH
Q.19 Which gland is known as the 'master gland' of the endocrine system?
Thyroid gland
Pituitary gland
Adrenal gland
Pineal gland
Explanation - The pituitary gland is called the master gland because it secretes hormones that regulate other endocrine glands.
Correct answer is: Pituitary gland
Q.20 Which hormone regulates blood glucose by lowering its concentration?
Glucagon
Insulin
Cortisol
Adrenaline
Explanation - Insulin decreases blood glucose by promoting glucose uptake into cells and stimulating glycogen synthesis.
Correct answer is: Insulin
Q.21 Where is the hormone melatonin primarily produced?
Pituitary gland
Pineal gland
Hypothalamus
Adrenal gland
Explanation - Melatonin is secreted by the pineal gland and helps regulate circadian rhythms.
Correct answer is: Pineal gland
Q.22 Which part of the adrenal gland secretes catecholamines such as adrenaline?
Adrenal cortex
Adrenal medulla
Zona glomerulosa
Zona fasciculata
Explanation - The adrenal medulla produces adrenaline and noradrenaline, crucial for the fight-or-flight response.
Correct answer is: Adrenal medulla
Q.23 Thyroxine (T4) and triiodothyronine (T3) are secreted by which gland?
Adrenal gland
Pituitary gland
Thyroid gland
Parathyroid gland
Explanation - The thyroid gland secretes T3 and T4, which regulate basal metabolic rate and growth.
Correct answer is: Thyroid gland
Q.24 Which hormone is secreted by the posterior pituitary gland?
Growth hormone
Oxytocin
Prolactin
TSH
Explanation - The posterior pituitary stores and releases oxytocin and ADH, though they are synthesized in the hypothalamus.
Correct answer is: Oxytocin
Q.25 Parathyroid hormone (PTH) increases blood levels of which ion?
Sodium
Calcium
Potassium
Magnesium
Explanation - PTH raises blood calcium levels by increasing bone resorption, renal calcium reabsorption, and vitamin D activation.
Correct answer is: Calcium
Q.26 Which hypothalamic hormone stimulates release of ACTH from the anterior pituitary?
CRH
TRH
GnRH
GHRH
Explanation - Corticotropin-releasing hormone (CRH) stimulates secretion of adrenocorticotropic hormone (ACTH).
Correct answer is: CRH
Q.27 Which pancreatic cells secrete glucagon?
Beta cells
Alpha cells
Delta cells
F cells
Explanation - Alpha cells in the islets of Langerhans secrete glucagon, which increases blood glucose.
Correct answer is: Alpha cells
Q.28 Which hormone is responsible for stimulating milk production?
Oxytocin
Prolactin
Estrogen
Progesterone
Explanation - Prolactin from the anterior pituitary stimulates milk synthesis in mammary glands.
Correct answer is: Prolactin
Q.29 Which endocrine gland regulates basal metabolic rate?
Adrenal gland
Thyroid gland
Pancreas
Pituitary gland
Explanation - Thyroid hormones regulate metabolism, growth, and development.
Correct answer is: Thyroid gland
Q.30 Which hormone promotes water reabsorption in the kidneys?
ADH
Aldosterone
Cortisol
PTH
Explanation - Antidiuretic hormone increases water reabsorption in the collecting ducts of the kidney.
Correct answer is: ADH
Q.31 Which hormone stimulates uterine contractions during labor?
Estrogen
Progesterone
Oxytocin
Relaxin
Explanation - Oxytocin promotes strong uterine contractions during childbirth.
Correct answer is: Oxytocin
Q.32 Which adrenal cortex zone produces mineralocorticoids like aldosterone?
Zona glomerulosa
Zona fasciculata
Zona reticularis
Medulla
Explanation - The zona glomerulosa produces aldosterone, which regulates sodium and potassium balance.
Correct answer is: Zona glomerulosa
Q.33 Which hormone regulates circadian rhythm?
Cortisol
Insulin
Melatonin
Thyroxine
Explanation - Melatonin, secreted by the pineal gland, regulates sleep-wake cycles.
Correct answer is: Melatonin
Q.34 Which hormone stimulates red blood cell production?
Erythropoietin
Prolactin
Cortisol
TSH
Explanation - Erythropoietin, produced by the kidneys, stimulates bone marrow to produce red blood cells.
Correct answer is: Erythropoietin
Q.35 Which pancreatic hormone inhibits both insulin and glucagon release?
Amylin
Somatostatin
C-peptide
Pancreatic polypeptide
Explanation - Somatostatin from delta cells inhibits both insulin and glucagon secretion.
Correct answer is: Somatostatin
Q.36 Which hormone is essential for female ovulation?
FSH
LH
Prolactin
Progesterone
Explanation - The LH surge triggers ovulation and corpus luteum formation.
Correct answer is: LH
Q.37 What is the primary function of calcitonin?
Increase calcium absorption
Decrease blood calcium
Increase blood calcium
Stimulate vitamin D synthesis
Explanation - Calcitonin, secreted by thyroid C cells, lowers blood calcium by inhibiting bone resorption.
Correct answer is: Decrease blood calcium
Q.38 Which hormone is responsible for stress adaptation and increases blood glucose?
Aldosterone
Cortisol
ADH
Thyroxine
Explanation - Cortisol increases gluconeogenesis, maintains blood pressure, and adapts the body to stress.
Correct answer is: Cortisol
Q.39 Which endocrine gland is located in the sella turcica?
Thyroid gland
Pituitary gland
Pineal gland
Adrenal gland
Explanation - The pituitary gland sits in the sella turcica of the sphenoid bone.
Correct answer is: Pituitary gland
Q.40 Which hormone regulates sodium reabsorption in the kidneys?
ADH
Aldosterone
PTH
Cortisol
Explanation - Aldosterone increases sodium reabsorption and potassium excretion in the distal nephron.
Correct answer is: Aldosterone
Q.41 Which hormone stimulates release of thyroid hormones from the thyroid gland?
ACTH
TSH
FSH
GH
Explanation - Thyroid-stimulating hormone (TSH) from the anterior pituitary stimulates secretion of T3 and T4.
Correct answer is: TSH
Q.42 Which hormone increases uterine lining thickness during the menstrual cycle?
Estrogen
Progesterone
LH
Prolactin
Explanation - Estrogen stimulates proliferation of the endometrium in the follicular phase.
Correct answer is: Estrogen
Q.43 Which endocrine organ is both exocrine and endocrine in function?
Pancreas
Adrenal gland
Thyroid gland
Pituitary gland
Explanation - The pancreas secretes digestive enzymes (exocrine) and hormones like insulin and glucagon (endocrine).
Correct answer is: Pancreas