When the postsynaptic cell is not depolarized,NMDA receptors
A)allow both sodium and calcium to enter the cell.
B)are blocked by a molecule of calcium.
C)are blocked by a molecule of magnesium
D)allow potassium to leave the cell.

Question

When the postsynaptic cell is not depolarized,NMDA receptors​ 
A)allow both sodium and calcium to enter the cell. 
B)are blocked by a molecule of calcium. 
C)are blocked by a molecule of magnesium 
D)allow potassium to leave the cell.

Quizplus · Accepted Answer

When the postsynaptic cell is not depolarized, NMDA receptors are blocked by a molecule of magnesium. This prevents calcium from entering the cell. Once the postsynaptic cell is depolarized, magnesium is expelled and both sodium and calcium can enter the cell through NMDA receptors.

When the Postsynaptic Cell Is Not Depolarized,NMDA Receptors​

When the Postsynaptic Cell Is Not Depolarized,NMDA Receptors