Assertion : Aldosterone is a steroid hormone and is important in the control of sodium and potassium ion concentration in mammals. Reason : It upgrades sodium ion concentration in the ECF by promoting reabsorption of sodium ions from renal tubules and excretion of potassium ions in urine.

Step-by-step solution

Aldosterone is a steroid hormone (mineralocorticoid) produced by the outer-section (zona glomerulosa) of the adrenal cortex in the adrenal gland to regulate sodium and potassium balance in the blood. Aldosterone hormone is produced in the cortex of adrenal gland (above the kidneys). This hormone affects body's ability to regulate blood pressure. It sends signals to the organs like kidney and colon, that can increase the amount of sodium that the body sends into the blood stream or the amount of potassium released i