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Cell Structure and Function: Kidney Nephrons

APBIO-4Y1GCG

In humans, kidneys function to remove metabolic waste materials and other toxins from the blood stream while simultaneously recovering key electrolytes and water from the filtrate. The functional cells of the kidney are called nephrons. Portions of the nephron called the Loops of Henle create a concentration gradient within the kidney for the purposes of osmoregulation.

Which of the following is a structural difference between cells of the descending Loop of Henle and cells of the ascending Loop of Henle that aids in conservation of water?

A

The plasma membranes of cells in the ascending loop have fewer aquaporins than do the plasma membranes of cells in the descending loop.

B

The plasma membranes of cells in the ascending loop contain more unsaturated phospholipids than are the plasma membranes of cells in the descending loop.

C

The cells of the ascending loop contain more smooth endoplasmic reticuli than do the cells of the descending loop.

D

The cells of the ascending loop have a greater surface area to volume ratio than do the cells of the descending loop.