Compared to type 1 (slow oxidative)skeletal muscle fibers,how are type 2X (fast-glycolytic)skeletal muscle fibers different?
A)Type 2X fibers have more abundant mitochondria.
B)Type 2X fibers fatigue more readily.
C)Type 2X fibers have more abundant myoglobin.
D)Type 2X fibers are smaller in diameter.
E)Type 2X motor units contain fewer fibers per alpha motor neuron.

Question

Compared to type 1 (slow oxidative)skeletal muscle fibers,how are type 2X (fast-glycolytic)skeletal muscle fibers different?
A)Type 2X fibers have more abundant mitochondria.
B)Type 2X fibers fatigue more readily.
C)Type 2X fibers have more abundant myoglobin.
D)Type 2X fibers are smaller in diameter.
E)Type 2X motor units contain fewer fibers per alpha motor neuron.

Quizplus · Accepted Answer

Type 2X fibers have less abundant mitochondria, less myoglobin, and a smaller diameter than type 1 fibers. However, they have a higher capacity for glycolysis, which allows them to generate ATP more quickly but also leads to quicker fatigue. Type 2X motor units contain more fibers per alpha motor neuron, which contributes to their greater force production capabilities.

Compared to Type 1 (Slow Oxidative)skeletal Muscle Fibers,how Are Type