Which of the Following Will Occur with a Decrease in the ECF

Question

Which of the following will occur with a decrease in the ECF volume? A)Increase in glomerular filtration rate (GFR) B)Increase in angiotensin II levels C)Increase in natriuretic peptide levels D)Increase in free H2O clearance E)Increase in fractional excretion of Na⁺

Accepted Answer

A decrease in ECF volume would activate the renin-angiotensin-aldosterone system (RAAS) in order to increase blood pressure and restore ECF volume. This would lead to an increase in angiotensin II levels. Option A is incorrect because a decrease in ECF volume would lead to a decrease in GFR as the body conserves water and solutes. Option C is incorrect because an increase in natriuretic peptide levels would occur in response to an increase in ECF volume, which would activate the body's natural diuretic response to reduce blood pressure and volume. Option D and E are unrelated to changes in ECF volume.