MUSCLE PHYSIOLOGY

PHYSIOLOGY

SKELETAL MUSCLE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The capacity of a muscle cell to shorten forcefully is known as
A
elasticity.
B
flexibility.
C
excitability.
D
contractility.
Explanation: 

Detailed explanation-1: -Contractility is the ability of muscle cells to forcefully shorten. For instance, in order to flex (decrease the angle of a joint) your elbow you need to contract (shorten) the biceps brachii and other elbow flexor muscles in the anterior arm.

Detailed explanation-2: -Contractility represents the ability of the myocardial muscle to shorten or thicken against a load. Although ejection fraction (EF) is the most common clinical assessment of contractility in practice, it is highly dependent on ventricular afterload.

Detailed explanation-3: -The correct option is A. Sarcomeres. During contraction, the ends of the sarcomeres are pulled closer together, thus shortening the length of the muscle fiber.

Detailed explanation-4: -The sarcomere of striated muscles. Depicted in Figure 1 is the sarcomere, which is the basic contractile unit of striated muscle.

There is 1 question to complete.