Endocrine Glands & Hormones — NEET Biology
📚 Practice ConceptThe pituitary hormones regulate the growth and development of somatic tissues and activities of peripheral endocrine glands. Pineal gland secretes melatonin, which plays a very important role in the regulation of 24-hour (diurnal) rhythms of our body (maintenance of the sleep-wake cycle, body temperature, etc.). The thyroid gland hormones play an important role in the regulation of the basal metabolic rate, development and maturation of the central nervous system, erythropoiesis, metabolism of carbohydrates, proteins and fats, menstrual cycle. Another thyroid hormone, i.e., thyrocalcitonin regulates calcium levels in our blood by decreasing it. The parathyroid glands secrete parathyroid hormone (PTH) which increases the blood Ca2+ levels and plays a major role in calcium homeostasis. The thymus gland secretes the hormone called thymosins which stimulates the T-lymphocytes, which provide cell-mediated immunity. In addition, thymosins also increase the production of antibodies to provide humoral immunity. The adrenal gland is composed of the centrally located adrenal medulla and the outer adrenal cortex. The adrenal medulla secretes adrenaline and noradrenaline. These hormones are rapidly secreted during emergency situations and are called 'fight, strength of heart contraction, rate of respiration, glycogenolysis, lipolysis, proteolysis. The adrenal cortex secretes glucocorticoids and mineralocorticoids. Glucocorticoids stimulate gluconeogenesis, lipolysis, proteolysis, erythropoiesis, cardiovascular system, blood pressure, and glomerular filtration rate and inhibit inflammatory reactions by suppressing the immune response. Mineralocorticoids regulate water and electrolyte contents of the body. The endocrine pancreas secretes two major hormones called insulin and glucagon. The imbalance of these results in hyperglycemia. Insulin stimulates cellular glucose uptake and utilisation, and glycogenesis resulting in hypoglycemia. Insulin deficiency and/or insulin resistance result in a disease called diabetes mellitus.
Which of the following statements regarding thyroid hormones and their functions are correct? S1: Thyroid hormones, T3 and T4, are vital for regulating the basal metabolic rate and the metabolism of carbohydrates, proteins, and fats. S2: The maintenance of water and electrolyte balance in the body is significantly influenced by thyroid hormones. S3: Hypothyroidism during adulthood primarily results in cretinism and deaf-mutism. S4: Hypersecretion of thyroid hormones increases the rate of red blood cell formation. S5: Exophthalmic goitre is characterized by an increase in body weight, decreased BMR, and accelerated heart rate.
View solution & NCERT explanation
Correct answer: B — S1, S2 and S4 only
S1 is correct. "Thyroid hormones play an important role in the regulation of the basal metabolic rate. These hormones control the metabolism of carbohydrates, proteins and fats." S2 is correct. "Maintenance of water and electrolyte balance is also influenced by thyroid hormones." S3 is incorrect. Cretinism and deaf-mutism are conditions caused by hypothyroidism during pregnancy or infancy, not adulthood. S4 is correct. "Thyroid hormones also support the process of red blood cell formation"; therefore, hypersecretion would increase this rate. S5 is incorrect. Exophthalmic goitre is characterized by weight loss and increased BMR, not weight gain and decreased BMR. Therefore, S1, S2, and S4 are correct. This question tests the comprehensive understanding of thyroid hormone functions and the symptoms associated with their imbalances.
What does NCERT say about pituitary hormones regulate growth?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.