Final answer:
The hormone secreted by the adrenal cortex in response to low dietary salt intake is aldosterone, which helps regulate sodium and water balance, affecting blood volume and pressure.
The adrenal cortex secretes the hormone aldosterone in response to low dietary salt intake
Step-by-step explanation:
The adrenal cortex secretes the hormone aldosterone in response to low dietary salt intake. Aldosterone, known as the "salt-retaining hormone", regulates sodium and water levels in the body, which impacts blood volume and blood pressure. It is released when there is a decrease in blood volume, blood pressure, or sodium levels, or when there is an increase in potassium levels. This hormone enhances the reabsorption of sodium ions in the kidney tubules while increasing the excretion of potassium ions. Its secretion is part of a larger mechanism involving the renin-angiotensin system, which is activated due to changes in blood pressure or plasma electrolyte composition, continuing the management of vital body fluid levels and blood pressure.