A person with diarrhoea loses excessive salt and water from the body. This loss results in Na⁺ depletion, dehydration, a decreased extracellular fluid volume, a reduction in plasma volume, and a decreased systemic arterial blood pressure.The following refer to the events that occur to compensate for this fluid loss. Match the effects, labelled a. through c., with the factors listed. (Options may be used more than once or not at all.)
-aldosterone secretion
A)exhibits no change
B)is increased
C)is decreased

Question

Quizplus · Accepted Answer

Diarrhoea causes Na⁺ depletion, which triggers the renin-angiotensin-aldosterone system (RAAS) to release aldosterone. Aldosterone stimulates the reabsorption of Na⁺ in the kidneys, which leads to an increase in blood volume and blood pressure.

Answer: C 
 Diarrhoea results in a decrease in extracellular fluid volume, which stimulates the release of antidiuretic hormone (ADH). ADH stimulates water reabsorption in the kidneys, which helps to increase blood volume. However, ADH also causes vasoconstriction, which can lead to a further decrease in blood pressure.

A Person with Diarrhoea Loses Excessive Salt and Water from the Body