Question

Describe the renin-angiotensin-aldosterone pathway.

a) Renin converts angiotensinogen to angiotensin I, which is then converted to angiotensin II by ACE, leading to vasoconstriction and aldosterone release.
b) Renin converts angiotensin II to angiotensin I, which is then converted to angiotensin III by ACE, leading to vasodilation and aldosterone release.
c) Renin converts angiotensinogen to angiotensin III, which is then converted to angiotensin II by ACE, leading to vasodilation and aldosterone release.
d) Renin converts angiotensin I to angiotensin II, which is then converted to angiotensin III by ACE, leading to vasoconstriction and aldosterone release.

Answer 1

The renin-angiotensin-aldosterone pathway involves renin converting angiotensinogen to angiotensin I, which is transformed into angiotensin II by ACE, causing vasoconstriction and aldosterone release for blood pressure regulation.

Step-by-step explanation:

The correct description of the renin-angiotensin-aldosterone pathway is option (a): Renin converts angiotensinogen to angiotensin I, which is then converted to angiotensin II by ACE, leading to vasoconstriction and aldosterone release. The process starts with specialized cells in the kidneys detecting a decrease in blood pressure or blood flow. These cells, which are part of the juxtaglomerular apparatus, secrete renin into the bloodstream. Renin catalyzes the conversion of angiotensinogen, a protein made by the liver, into angiotensin I. This molecule then travels to the lungs, where ACE (angiotensin-converting enzyme) converts it to angiotensin II. Angiotensin II is a potent vasoconstrictor that raises blood pressure and stimulates the adrenal cortex to release aldosterone. Aldosterone, in turn, leads to increased sodium and water reabsorption in the kidneys, further aiding in blood pressure stabilization.