Question

Identify label ‘X’ from the given diagram and name the cells, which regulate concentration of calcium and phosphorous in the blood and select the correct option given below.

Options

• Thyroid gland − Parafollicular cells

• Thyroid gland − Sertoli cells

• Parathyroid gland − Acidophils

• Parathyroid gland − chromatophores

Answer 1

Thyroid gland − Parafollicular cells

Explanation:

Label ‘X’ identifies the thyroid gland, which contains specialised parafollicular cells (also known as C-cells). These cells secrete the hormone calcitonin, which lowers blood calcium levels by inhibiting bone resorption and increasing calcium excretion by the kidneys.