Skeletal Muscle System

These flashcards cover key vocabulary related to the anatomy, structure, and function of skeletal muscles.

Muscle Fiber

Long, cylindrical, multinucleated cell that makes up skeletal muscle.

Sarcoplasm

The volume within muscle fibers that contains glycogen and myoglobin, the latter being a red-colored protein that binds oxygen.

Epimysium

Connective tissue that surrounds the entire muscle.

Perimysium

Connective tissue that surrounds individual fascicles.

Endomysium

Connective tissue that surrounds individual muscle fibers.

Tendon

A structure that attaches muscle to bone.

Aponeurosis

A flat sheet that attaches muscle to bone or muscle to muscle.

Sarcomere

The basic functional unit of striated muscle, composed of overlapping thick and thin filaments.

Motor Unit

A nerve cell (neuron) and the muscle cells it stimulates.

Prime Mover

A muscle that has major responsibility for a particular movement.

Antagonist

A muscle that opposes the action of the prime mover.

Synergist

A muscle that assists the prime mover, stabilizing a joint during the movement.

Fixator

A muscle that stabilizes the origin of a muscle or a bone to which the origin is attached.

Fascicle

A bundle of muscle fibers.

Striated Muscle

Muscle tissue that has a striped appearance due to the arrangement of myofibrils.

I Band

The lighter region of the sarcomere that contains only thin filaments.

A Band

The darker region of the sarcomere that contains thick and thin filaments.

Skeletal Muscle Activity

The process by which skeletal muscles contract and produce movement.