What role does the adrenal cortex play in electrolyte balance?

The adrenal cortex plays a crucial role in maintaining electrolyte balance primarily through the secretion of mineralocorticoids, with aldosterone being the most notable among them. Aldosterone regulates sodium and potassium levels in the body. It promotes the reabsorption of sodium from the urine back into the bloodstream, which increases sodium levels and helps to maintain blood pressure and fluid balance. Conversely, it facilitates the excretion of potassium, helping to maintain normal potassium levels. This action is vital for cardiovascular health and overall homeostasis.

The other options involve functions that are not related to the adrenal cortex's role in electrolyte balance. Insulin and glucagon are hormones secreted by the pancreas that primarily regulate blood glucose levels, while adrenaline (also known as epinephrine) is produced by the adrenal medulla and is involved in the body's fight-or-flight response, not directly related to electrolyte balance.