Question

Which of the following options is correct for secretion of regions labelled as “a” and “b” in the given diagram?

• A. a - Aldosterone b - Cortisol
• B. a - Cortisol b - Adrenaline
• C. a - ADH b - Noradrenaline
• D. a - Norepinephrine b - Cortisol

Answer 1

The correct option is B a - Cortisol b - Adrenaline

Adrenal glands are present on top of the kidneys. Adrenal cortex and adrenal medulla are two divisions of the adrenal gland. ‘a’ is adrenal cortex (outer region) and ‘b’ is adrenal medulla (inner region) of the adrenal gland.

The adrenal cortex secretes hormones called corticoids. The corticoids, which are involved in carbohydrate metabolism, are called glucocorticoids. Cortisol is the main glucocorticoid in our body. Corticoids, which regulate the balance of water and electrolytes in our body are called mineralocorticoids. Aldosterone is the main mineralocorticoid in our body.

The adrenal medulla secretes two hormones called adrenaline or epinephrine and noradrenaline or norepinephrine. These are called catecholamines. These hormones are released in response to a stressful situation and are also known as emergency hormones. They increase heart rate, the rate of contraction of heart, rate of respiration enabling the body to deal with emergency situations.
ADH also called vasopressin is synthesised by hypothalamus but secreted by posterior pituitary.