Explain how the cycling of sodium chloride between the descending and ascending limbs of the loop of Henle in the mammalian kidney, and special permeability of these tubules, produces high osmotic concentrations in interstitial fluids in the kidney medulla. Explain the role of urea in producing high osmotic concentrations in the intersti-tial fluid of the medulla.

Describe what happens during the following stages in urine forma-tion in the mammalian nephron: filtration, tubular reabsorption, tubular secretion.

Physiology of angiotensin II in humans     Angiotensin I is enzymatically converted to angiotensin II by ACE.   Angiotensinogen II acts on the adrenal cortex to cause the release of storage vesicles containing aldosterone.   Angiotensin II is a peptide hormone that is made in advance and stored in vesicles. Physiology of angiotensin II in humans   Question 24 options:   Angiotensin I is enzymatically converted to angiotensin II by ACE.   Angiotensinogen II acts on the adrenal cortex to cause the release of storage vesicles containing aldosterone.   Angiotensin II is a peptide hormone that is made in advance and stored in vesicles.