Figure 39.1 -

question 27

Multiple Choice

Figure 39.1
-
Answer the question using the accompanying figure. At which point in this action potential diagram are Na⁺inactivation gates opening?

• A) A
• B) B
• C) C
• D) D
• E) E

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Definitions:

Posterior Deep Pectoralis Major

The deeper part of the pectoralis major muscle, situated at the back, instrumental in the movement of the shoulder and upper arm.

Superficial Pectoral

Refers to the muscles located at the front of the chest, involved in the movement of the shoulders and arms.

Sartorius

The longest muscle in the human body, running down the length of the thigh; it helps in flexing, abduction, and lateral rotation of the hip.

Gracilis

A slender muscle in the inner thigh, contributing to the adduction of the hip and flexion of the knee.