Q60. The hormone secretin is produced primarily by which organ?
[WBCS Mains, Science, 2023]
(A) Stomach
(B) Liver
(C) Small intestine
(D) Pancreas
Answer: (C) Small intestine
Explanation: S cells of the duodenal mucosa release secretin in response to acidic chyme. Secretin stimulates bicarbonate-rich pancreatic and biliary secretions that help neutralise acid entering the small intestine, thereby allowing intestinal digestive enzymes to work efficiently.
Q59. Which hormone is secreted by beta cells of the pancreatic islets of Langerhans?
[UPPSC PCS Preliminary Examination, 14 May 2023]
(A) Adrenaline
(B) Glucagon
(C) Insulin
(D) Aldosterone
Answer: (C) Insulin
Explanation: Pancreatic beta cells secrete insulin, which promotes cellular uptake and storage of glucose and lowers blood sugar. Alpha cells secrete glucagon, while delta cells release somatostatin. Dysfunction or destruction of beta cells is central to diabetes mellitus.
Q58. Match the disorders with the correct gland or hormone:
(i) Addison disease, (ii) Hashimoto disease, (iii) acromegaly, (iv) SIADH;
(a) adrenal gland, (b) thyroid gland, (c) growth hormone, (d) vasopressin.
[SSC CGL Tier I, 24 July 2023, Shift 1]
(A) i-b, ii-a, iii-d, iv-c
(B) i-b, ii-c, iii-a, iv-d
(C) i-a, ii-b, iii-c, iv-d
(D) i-d, ii-c, iii-b, iv-a
Answer: (C) i-a, ii-b, iii-c, iv-d
Explanation: Addison disease commonly involves adrenal cortical insufficiency; Hashimoto disease is autoimmune thyroiditis. Acromegaly results from excessive growth hormone after growth plates close. SIADH means inappropriate excess antidiuretic hormone, also called vasopressin, producing water retention.
Q57. Which of the following disease–hormone pairs is incorrectly matched?
[SSC CGL Tier I, 21 July 2023, Shift 4]
(A) Cushing syndrome—cortisol
(B) Diabetes mellitus—insulin
(C) Goitre—thyroxine
(D) Acromegaly—adrenaline
Answer: (D) Acromegaly—adrenaline
Explanation: Acromegaly is caused by excess growth hormone, usually due to a pituitary adenoma, not adrenaline. Cushing syndrome reflects excessive glucocorticoid exposure, and diabetes mellitus involves impaired insulin secretion or action. Goitre means enlarged thyroid, with various possible hormone levels.
Q56. Goitre is a disorder involving which gland?
[SSC MTS Examination, 20 June 2023, Shift 2]
(A) Thyroid gland
(B) Pituitary gland
(C) Pancreas
(D) Adrenal gland
Answer: (A) Thyroid gland
Explanation: Goitre means enlargement of the thyroid, located in the anterior neck. Iodine deficiency is a classic cause, though autoimmune disorders and nodules can also produce it. Thyroid hormone levels may be low, normal or high depending on the cause.
Q55. Which substance is essential for the thyroid gland to manufacture thyroxine?
[UPSC CDS I, General Knowledge, 16 April 2023]
(A) Sodium chloride
(B) Potassium chloride
(C) Cholesterol
(D) Iodine
Answer: (D) Iodine
Explanation: Thyroid follicular cells use dietary iodine and the amino acid tyrosine to make T3 and T4. The names indicate three or four iodine atoms, respectively. Without sufficient iodine, hormone synthesis falls and the thyroid may enlarge under sustained TSH stimulation.
Q54. Which hormone can rapidly increase heartbeat during an emergency?
[UPSC NDA II, General Ability Test, 4 September 2022]
(A) Insulin
(B) Melatonin
(C) Thyroxine
(D) Adrenaline
Answer: (D) Adrenaline
Explanation: Adrenaline is released from the adrenal medulla during sympathetic activation. It raises heart rate and cardiac output, dilates airways and mobilises energy stores. These immediate effects form part of the fight-or-flight response to sudden threat or exertion.
Q53. Which mineral is required for formation of thyroxine?
[RRB Group D, 30 August 2022, Shift 3]
(A) Iron
(B) Calcium
(C) Iodine
(D) Potassium
Answer: (C) Iodine
Explanation: Thyroxine is tetraiodothyronine, abbreviated T4, and contains four iodine atoms. The thyroid requires dietary iodine to synthesise its hormones. Iodine deficiency is associated with thyroid enlargement and potentially impaired physical and neurological development during early life.
Q52. Which of the following is NOT a ductless endocrine gland?
[RRB Group D, 29 August 2022, Shift 1]
(A) Pituitary gland
(B) Salivary gland
(C) Adrenal gland
(D) Thyroid gland
Answer: (B) Salivary gland
Explanation: Salivary glands are exocrine: their secretions enter the mouth through ducts. The pituitary, adrenal and thyroid glands are endocrine and release hormones into the blood. An organ such as the pancreas contains both endocrine and exocrine tissue.
Q51. Which hormone helps the body respond immediately when a person is angry, frightened or worried?
[RRB Group D, 28 September 2022, Shift 2]
(A) Adrenaline
(B) Thyroxine
(C) Oestrogen
(D) Testosterone
Answer: (A) Adrenaline
Explanation: Adrenaline, or epinephrine, is a catecholamine released rapidly by adrenal medullary cells. It prepares the body for action by increasing heart rate, opening airways and directing more blood to active muscles. Cortisol supports a slower, longer-lasting stress response.
