Select the correct statement about hormones and their actions.

• Parathyroid hormone increases K absorption of the body.

• Insulin and glucagon helps to maintain blood sugar levels.

• Old aged people have weak immunity due to increased activity of thymus.

• Osteoporosis in women occurs due to increased levels of oestrogens.

B.

Insulin and glucagon helps to maintain blood sugar levels.

Parathyroid hormone (PTH) stimulates the reabsorption of Ca by renal tubules and increases Ca²⁺ absorption from digested food. It means PTH increases the blood Ca²⁺ level.

Old aged persons have weak immunity because thymus is degenerated in old individuals resulting in a decreased production of thymosin and poor immunity.

Oestoporosis in women occurs due to decreased level of estrogen.