THORAX ABDOMEN AND PELVIS

MEDICAL

KIDNEY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which statement best explains the flow of materials out of the nephron?
A
The active transport of Na+ (and thus Cl-) creates salt, which pulls water using a concentration gradient in an attempt to create equilibrium
B
The high pressure from the renal artery creates a force that pushes water through permeable areas, which creates an equilibrium in pressure
C
There is no explanation. The kidneys work randomly and it is amazing that they function correctly.
D
Water is actively transported out of the nephron and the nephron compensates by actively pushing out ions in an attempt to balance the charges
Explanation: 

Detailed explanation-1: -The glomerulus is the site in the nephron where fluid and solutes are filtered out of the blood to form a glomerular filtrate. The proximal and distal tubules, the loop of Henle, and the collecting ducts are sites for the reabsorption of water and ions.

Detailed explanation-2: -Proximal convoluted tubule is involved in active reabsorption of sodium. The majority (about 70%) of sodium is reabsorbed here, into the cytosol of the epithelial cells of the nephron.

Detailed explanation-3: -Sodium is actively pumped out, while potassium and chloride diffuse down their electrochemical gradients through channels in the tubule wall and into the bloodstream. The walls of the thick ascending limb are impermeable to water, so in this section of the nephron water is not reabsorbed along with sodium.

There is 1 question to complete.