Exam 9: Skeletal Muscle: Structure and Function

High activity of the enzyme ATPase is found in both slow-twitch (type I)and fast-twitch (type IIx)fibers.

The motor neuron and all the muscle fibers it innervates is called a ______.

Which of the following has been shown to cause muscle fatigue?

The specific tension (i.e. ,force production per cross sectional area of the fiber)differs between fiber types.Which of the following answers is correct in regard to specific force production?

A highly successful endurance athlete would likely have ________________ compared to a sedentary person.

Skeletal muscle fibers that contain moderate-to-high numbers of mitochondria could be classified as

Age-related loss of skeletal muscle mass is called sarcopenia.

A popular belief among many athletes and coaches is that exercise-induced muscle cramps in a single muscle (e.g. ,gastrocnemius)results from dehydration and blood electrolyte imbalance.Which of the following observations DO NOT support this position?

A muscular contraction that results in a movement of body parts is called a(n)

Fast-twitch fibers (i.e. ,type IIx)contain a relatively

Satellite cells

Abundant evidence indicates that rigorous exercise training can result in a conversion of muscle fiber type.

The connecting point between a motor neuron and muscle cell is called the

During muscle relaxation (following a muscle contraction),calcium is moved back into the sarcoplasmic reticulum via simple diffusion.

The two principal contractile proteins found in skeletal muscle are

The layer of connective tissue that surrounds the outside of skeletal muscle (i.e. ,just below the fascia)is called the

Which of the following events occurs first during a voluntary muscle contraction?

One of the proposed mechanisms to explain the positive impact of postactivation potential on muscle performance is that low intensity muscle contractions results in phosphorylation of myosin light chains (i.e. ,proteins located at the base of the myosin cross-bridge).This increased phosphorylation can increase muscle force production by

The formation of cross-bridges that initiates the contractile process in skeletal muscle is triggered by

Disease-related muscle wasting is referred to as