Question

Sodium potassium pumps and sodium glucose co-transporters (symporter) are both found in the plasma membrane of intestinal cells. describe two similarities and one difference between these two transporters that relates to how they function.

Note: the molecules being transported and positioning in the membrane may not be used as a similarity or difference.

Answer 1

Ans. Difference -

In Sodium potassium pump, for every 3 sodium ions transported out of the cell, 2 potassium ions are transported inside cell. In the process, the pump helps to stabilize membrane potential, and thus is essential in creating the conditions necessary for the firing of action potentials.

In Sodium glucose symport, both sodium and glucose move in same direction. It is responsible for glucose absorption in the small intestine, and for reabsorbing nearly 3% of the filtered glucose load in the renal proximal tubule segment.

Similarities -

They both fuction in combined manner, i.e., after one another. Firstly the sodium potassium pump transfers the sodium ion outside the cell using ATP, this action creates a downhill sodium ion gradient from the outside to the inside of the proximal tubule cell. The symporter use this downhill sodium gradient to transport glucose across aapical membrane, against uphill gradient.

These are both types of active transport. Sodium potassium pump is primary active transport, whereas sodium glucose cotransport is secondary active transport.