Class 11 Biology (NCERT / JAC Board)

1. Glands that lack ducts and secrete their chemical messengers directly into the bloodstream are called:

• A. Endocrine glands
• B. Exocrine glands
• C. Heterocrine glands
• D. Merocrine glands

2. Which master structure connects the nervous system to the endocrine system and regulates the pituitary gland?

• A. Hypothalamus
• B. Epithalamus
• C. Thalamus
• D. Pineal gland

3. The anterior lobe of the pituitary gland (Adenohypophysis) is connected to the hypothalamus via a:

• A. Portal circulatory system
• B. Direct neural connection
• C. Lymphatic system
• D. Glial bridge

4. Posterior pituitary (Neurohypophysis) stores and releases which two hormones produced by the hypothalamus?

• A. Oxytocin and Vasopressin (ADH)
• B. Growth Hormone and Prolactin
• C. ACTH and TSH
• D. FSH and LH

5. Hypersecretion of Growth Hormone (GH) in adults leads to severe disfigurement, particularly of the face, called:

• A. Acromegaly
• B. Gigantism
• C. Pituitary Dwarfism
• D. Cretinism

6. Which hormone stimulates milk synthesis and growth of mammary glands in females?

• A. Prolactin (PRL)
• B. Oxytocin
• C. Luteinizing Hormone (LH)
• D. Estrogen

7. The hormone that regulates the 24-hour (diurnal) rhythm of the human body, such as sleep-wake cycles, is:

• A. Melatonin
• B. Melanocyte Stimulating Hormone (MSH)
• C. Calcitonin
• D. Thyroxine

8. Deficiency of iodine in diet leads to enlargement of the thyroid gland, commonly known as:

• A. Goitre
• B. Addison’s disease
• C. Cushing’s syndrome
• D. Acromegaly

9. Hypothyroidism during pregnancy causes stunted growth, mental retardation, and low IQ in infants, termed:

• A. Cretinism
• B. Myxedema
• C. Grave’s disease
• D. Dwarfism

10. Thyroid hormone that lowers blood calcium levels by promoting calcium deposition in bones is:

• A. Thyrocalcitonin (TCT)
• B. Parathyroid Hormone (PTH)
• C. Tetraiodothyronine (T4)
• D. Triiodothyronine (T3)

11. Parathyroid hormone (PTH) increases blood Ca2+ levels, making it a:

• A. Hypercalcemic hormone
• B. Hypocalcemic hormone
• C. Hypoglycemic hormone
• D. Hyperglycemic hormone

12. Which gland plays a major role in differentiation of T-lymphocytes and development of cell-mediated immunity?

• A. Thymus
• B. Thyroid
• C. Adrenal
• D. Pancreas

13. Emergency hormones or fight-or-flight hormones (Adrenaline and Noradrenaline) are secreted by the:

• A. Adrenal medulla
• B. Adrenal cortex
• C. Anterior pituitary
• D. Hypothalamus

14. Cortisol, the primary glucocorticoid secreted by the adrenal cortex, is involved in:

• A. Stimulating gluconeogenesis, lipolysis, and anti-inflammatory responses
• B. Regulating sodium and water balance only
• C. Decreasing heart rate and blood pressure
• D. Lowering blood glucose levels

15. The main mineralocorticoid in humans that regulates electrolyte and water balance in renal tubules is:

• A. Aldosterone
• B. Cortisol
• C. Adrenaline
• D. Melatonin

16. Underproduction of adrenal cortex hormones alters carbohydrate metabolism and causes severe weakness called:

• A. Addison’s disease
• B. Cushing’s disease
• C. Diabetes insipidus
• D. Grave’s disease

17. Insulin is a peptide hormone secreted by which cells of the Islets of Langerhans?

• A. Beta cells (β-cells)
• B. Alpha cells (α-cells)
• C. Delta cells (δ-cells)
• D. F cells

18. Prolonged hyperglycemia and presence of glucose (glycosuria) and ketone bodies in urine are symptoms of:

• A. Diabetes mellitus
• B. Diabetes insipidus
• C. Addison’s disease
• D. Diabetes dwarfism

19. Glucagon raises blood glucose levels by promoting:

• A. Glycogenolysis and gluconeogenesis
• B. Glycogenesis and lipogenesis
• C. Cellular glucose uptake
• D. Protein synthesis

20. Leydig cells (interstitial cells) present in testes produce male sex hormones called:

• A. Androgens (e.g., Testosterone)
• B. Estrogens
• C. Progesterone
• D. Corticoids

21. Ruptured Graafian follicle transforms after ovulation into a yellow endocrine structure called:

• A. Corpus luteum
• B. Corpus albicans
• C. Corpus callosum
• D. Macula lutea

22. Which hormone maintains pregnancy and supports uterine lining development?

• A. Progesterone
• B. Luteinizing Hormone
• C. Oxytocin
• D. Prolactin

23. Atrial wall of the heart secretes a peptide hormone that reduces blood pressure, called:

• A. Atrial Natriuretic Factor (ANF)
• B. Erythropoietin
• C. Renin
• D. Gastrin

24. Juxtaglomerular (JG) cells of kidneys produce which peptide hormone to stimulate RBC formation (erythropoiesis)?

• A. Erythropoietin
• B. Renin
• C. Secretin
• D. Angiotensinogen

25. Which gastrointestinal hormone stimulates the secretion of water and bicarbonate ions from the exocrine pancreas?

• A. Secretin
• B. Gastrin
• C. Cholecystokinin (CCK)
• D. Gastric Inhibitory Peptide (GIP)

26. Cholecystokinin (CCK) acts on which two organs to stimulate digestive secretions?

• A. Gall bladder and Pancreas
• B. Stomach and Liver
• C. Small intestine and Large intestine
• D. Kidneys and Heart

27. Peptide and protein hormones (like insulin, glucagon, pituitary hormones) act on target cells by binding to:

• A. Membrane-bound receptors
• B. Intracellular receptors
• C. Nuclear receptors
• D. Mitochondrial receptors

28. Which of the following functions as a classic secondary messenger in peptide hormone action?

• A. Cyclic AMP (cAMP)
• B. DNA
• C. RNA
• D. Steroid nucleus

29. Steroid hormones (like estrogen, progesterone, cortisol, testosterone) exert action primarily by binding to:

• A. Intracellular/Nuclear receptors
• B. Cell surface G-protein receptors
• C. Transmembrane ion channels
• D. Extracellular matrix proteins

30. Hyperthyroidism characterized by thyroid enlargement, loss of weight, and protrusion of eyeballs is called:

• A. Exophthalmic goitre (Grave’s disease)
• B. Simple goitre
• C. Addison’s disease
• D. Hashimoto’s thyroiditis