Question

What are the stages the membrane potential goes through during an action potential? Describe each stage in terms of the changes in sodium and potassium ions inside the cell. Name and describe the two types of refractory periods, and what, if anything would make a neuron fire during a refractory period.

Answer 1

Depolarization, repolarization, hyperpolarization are the stages the membrane potential goes through during an action potential. During depolarization, Na+ channels opens which makes inside of membrane more positive than RMP. During repolarisation, Na+ channels are inactivated, K+ channels which opens AP spike stops rising, membrane returns to RMP. During hyperpolarization, some K+ channels remain open, Na+ channels reset, inside of membrane becomes more negative than RMP.

The two types of refractory period are absolute and relative refractory period.