Q30. Adrenaline is best classified as which of the following?
[SSC CGL, 16 August 2017, Shift 3]
(A) Hormone
(B) Digestive enzyme
(C) Vitamin
(D) Storage fat
Answer: (A) Hormone
Explanation: Adrenaline is a catecholamine hormone released into the blood by adrenal medullary chromaffin cells. It is also used as a neurotransmitter in some contexts. Its systemic action increases heart activity, airway dilation and glucose availability during emergencies.
Q29. Which of the following is NOT a plant hormone?
[SSC CGL, 10 August 2017, Shift 1]
(A) Gibberellin
(B) Auxin
(C) Cytokinin
(D) Thyroxine
Answer: (D) Thyroxine
Explanation: Thyroxine is an animal thyroid hormone that regulates metabolism and development. Auxins, cytokinins and gibberellins are plant growth regulators involved in processes such as cell elongation, cell division, stem growth and seed germination.
Q28. Which hormone–function pair is incorrectly matched?
[UPPSC PCS Preliminary Examination 2017]
(A) Insulin—blood-glucose regulation
(B) Melatonin—sleep timing
(C) Oxytocin—milk ejection
(D) Gastrin—blood-pressure regulation
Answer: (D) Gastrin—blood-pressure regulation
Explanation: Gastrin is secreted chiefly by G cells of the gastric antrum and stimulates stomach acid secretion. It is not primarily a blood-pressure regulator. Insulin acts in glucose homeostasis, melatonin in circadian timing, and oxytocin in milk let-down.
Q27. Insulin influences metabolism of which of the following nutrients?
[BPSC 63rd Preliminary Examination 2017]
(A) Fats only
(B) Carbohydrates only
(C) Proteins only
(D) Carbohydrates, fats and proteins
Answer: (D) Carbohydrates, fats and proteins
Explanation: Insulin regulates much more than blood glucose. It promotes glycogen synthesis, fat storage and protein synthesis while inhibiting several catabolic pathways. Thus carbohydrates, lipids and proteins all respond to insulin signalling, especially after a meal.
Q26. Insulin is chemically classified as a type of what?
[BPSC 60th–62nd Preliminary Examination 2016]
(A) Fat
(B) Vitamin
(C) Carbohydrate
(D) Protein
Answer: (D) Protein
Explanation: Human insulin is a peptide hormone consisting of two chains with a total of 51 amino acids linked by disulphide bonds. It is therefore a protein in biochemical classification and lowers blood glucose through receptor-mediated effects.
Q25. Which hormone is used as an emergency treatment for a severe allergic reaction with a dangerous fall in blood pressure?
[RPSC Senior Teacher Grade II Science Examination 2015]
(A) Insulin
(B) Adrenaline
(C) Thyroxine
(D) Melatonin
Answer: (B) Adrenaline
Explanation: Adrenaline rapidly supports blood pressure, reduces airway swelling and relaxes bronchial smooth muscle during anaphylaxis. It is first-line emergency treatment for that condition. The original examination described a marked fall in blood pressure more generally; clinical treatment depends on its cause.
Q24. Iodine is essential for the synthesis of which hormone?
[RPSC Senior Teacher Grade II Science Examination 2015]
(A) Adrenaline
(B) Insulin
(C) Thyroxine
(D) Testosterone
Answer: (C) Thyroxine
Explanation: The thyroid incorporates iodine into thyroxine and triiodothyronine. The other options are an adrenal catecholamine, a pancreatic peptide, and a steroid androgen. Dietary iodine deficiency can lead to reduced thyroid-hormone synthesis and thyroid enlargement.
Q23. Insulin is best described chemically as a:
[UPPSC PCS Mains Examination 2015]
(A) Steroid
(B) Carbohydrate
(C) Protein
(D) Fat
Answer: (C) Protein
Explanation: Insulin contains amino-acid chains, making it a peptide or protein hormone. It binds cell-surface receptors and affects carbohydrate, lipid and protein metabolism. It is not a steroid, which is a cholesterol-derived hormone class.
Q22. Which of the following is a plant hormone?
[CGPSC Preliminary Examination 2014 (held 7 June 2015)]
(A) Insulin
(B) Thyroxine
(C) Oestrogen
(D) Cytokinin
Answer: (D) Cytokinin
Explanation: Cytokinins are plant growth regulators that stimulate cell division and influence shoot development and leaf ageing. Insulin, thyroxine and oestrogen are animal hormones. The recruitment-exam cycle was labelled 2014, although its paper was administered in 2015.
Q21. Which hormone naturally exists as a gas under ordinary conditions?
[CGPSC Preliminary Examination 2013 (held 8 June 2014)]
(A) Abscisic acid
(B) Ethylene
(C) Gibberellin
(D) Auxin
Answer: (B) Ethylene
Explanation: Ethylene is a gaseous plant hormone associated with fruit ripening, senescence and responses to stress. The remaining options are other classes of plant growth regulators but are not normally gaseous. This is a plant-hormone comparison rather than a human endocrine-gland question.
