Answer to the two questions from the last lecture

Q1: Why do they need to know the mean arterial pressure?

A1: Because that's the best measurement of the perfusion of the body. For most practical purposes, the skilled clinician will know how to calculate an estimate of the mean-pressure based on systolic and diastolic pressure

Q2: Will repolarization occur in the opposite direction of the depolarization?

A2: Yes, in fact the repolarization will occur in the opposite direction but also with an opposite sign of the change in voltage. The first tissue that depolarizes will be the last to repolarize. Why? Because of different duration of the action potential, which is a result of different numbers of K+ gates in the cell membrane.