Parathyroid Glands & PTH Regulation — NEET Biology
📚 Practice ConceptIn humans, four parathyroid glands are present on the back side of the thyroid gland, one pair each in the two lobes of the thyroid gland. The parathyroid glands secrete a peptide hormone called parathyroid hormone (PTH). The secretion of PTH is regulated by the circulating levels of calcium ions.
Which of the following statements regarding parathyroid glands and their hormones are correct? S1: The parathyroid glands are embedded on the dorsal side of the thyroid gland, usually as four small structures. S2: Parathyroid Hormone (PTH) is a peptide hormone that enhances the reabsorption of calcium ions by the renal tubules. S3: PTH is a hypocalcemic hormone as it promotes bone formation and deposition of calcium. S4: Thyrocalcitonin (TCT) secreted by the thyroid gland, acts to decrease blood calcium levels by inhibiting bone resorption. S5: Along with TCT, PTH plays a significant role in maintaining the overall calcium balance in the body.
View solution & NCERT explanation
Correct answer: C — S1, S2, S4 and S5 only
S1 is correct. The NCERT states, "In humans, four parathyroid glands are present on the back side of the thyroid gland, one pair each in the two lobes of the thyroid gland." S2 is correct. "PTH also stimulates reabsorption of Ca2+ by the renal tubules." S3 is incorrect because PTH is a hypercalcemic hormone that stimulates bone resorption, not formation, to increase blood calcium levels. S4 is correct. Thyrocalcitonin (TCT) is secreted by the thyroid gland and acts to decrease blood calcium levels. S5 is correct. "Along with TCT, it plays a significant role in calcium balance in the body." Therefore, statements S1, S2, S4, and S5 are correct. The core concept tested is the function and regulation by parathyroid hormone and its interaction with TCT in calcium homeostasis.
What does NCERT say about humans four parathyroid glands?
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.