Skeletal Muscle

Chapter 9

Muscular System

Part A

2. List the three types of muscle tissue.

The three types of muscle tissue are: skeletal, smooth, and cardiac.

3. Distinguish between a tendon and an aponeurosis.

A tendon is a projection of connective tissue beyond the ends of the muscle that attaches to bone. An aponeurosis is a broad fibrous sheet of connective tissue that connects muscles to adjacent muscles.

4. Describe the connective tissue coverings of a skeletal muscle.

Muscle fibers are grouped together in fascicles that are surrounded by a layer of connective tissue called the endomysium. The fascicles are bundled together and surrounded by another layer of connective tissue called the perimysium, which also fills the spaces between the fascicles. Several layers of fibrous connective tissue called the epimysium, which surrounds the entire muscle, then cover the perimysium.

5. Distinguish between deep fascia, subcutaneous fascia, and subserous fascia.

Deep fascia is the portion of the network of the fasciae that surrounds and penetrates the muscles. Subcutaneous fascia is the portion that lies just beneath the skin forming the subcutaneous layer. Subserous fascia is the portion that forms the connective tissue layer of the serous membranes covering organs in various body cavities and lining those cavities.

6. List the major parts of a skeletal muscle fiber, and describe the function of each part.

A muscle fiber is a single, multinucleated cell, which contracts when stimulated. It is a thick, elongated cylinder with rounded ends that may extend the entire length of the muscle. Its component parts are:

Sarcolemma—The specific name for a muscle fiber’s cell membrane.

Sarcoplasm—The specific name for a muscle fiber’s cytoplasm. It contains the many small, oval nuclei and mitochondria.

Myofibrils—The numerous, threadlike proteins that lie parallel to one another and are contained in the sarcoplasm. The arrangement of the two proteins below...