Q: The outer surface of the heart changes from positive to negative during what?


Read this paragraph and choose the correct option from the provided answers:

Figure 20.33 The outer surface of the heart changes from positive to negative during depolarization. This wave of depolarization is spreading from the top of the heart and is represented by a vector pointing in the direction of the wave. This vector is a voltage (potential difference) vector. Three electrodes, labeled RA, LA, and LL, are placed on the patient. Each pair (called leads I, II, and III) measures a component of the depolarization vector and is graphed in an ECG.

 Choices:

- inflammation

- permeability

- reproduction

- depolarization


A:
depolarization