BIO 242 Study Guide - Midterm Guide: Resting Potential, Neurotransmitter Receptor, Axon Terminal
Document Summary
Describe the electrical properties of the plasma membrane. Membrane is polarized (difference in charge) meaning it has potential. If the inside and outside were both negative (or positive) there would be no potential because it wouldn"t be polarized. Anions don"t diffuse through the membrane so they stay inside the icf making it negatively charged. When mv increases the icf is depolarizing and when mv decreases icf is repolarizing. Na+ 3 pumped out k+ 2 pumped in. More k+ diffuses out because it has 25x more leaky channels than na+ also the neural membrane is more permeable to k+, this creates the slightly negative membrane resting potential. Less na+ can get out of the cell because it has less open ion channels for it to enter and the membrane isn"t as permeable to na+ So the na/k+ pump tries to restore the balance by pushing k+ and releasing na+ to restore each ion in their concentration.
