Skeletal Muscle and Muscle Spindle Anatomy

Vocabulary terms covering the histological structures of skeletal muscle and muscle spindles identified in Figure 6.4.

Fascicles

Small bundles of skeletal muscle fibers.

Skeletal muscle fibers

The individual cells that compose skeletal muscle tissue.

Extrafusal fibers

The standard skeletal muscle fibers found outside the muscle spindle that are responsible for muscle contraction.

Muscle spindle

A specialized sensory organ within the skeletal muscle that detects muscle stretch and length.

Perimysium

A layer of connective tissue that surrounds and groups individual muscle fibers into fascicles.

Arterioles

Small branches of arteries that lead into capillaries within the muscle tissue.

Endomysium

A fine layer of connective tissue that wraps each individual muscle fiber.

Capsule of muscle spindle

The connective tissue sheath that encloses the internal components of a muscle spindle.

Nerve fibers with Schwann cells

Peripheral nerve components located within the muscle tissue where Schwann cells provide support or insulation.

Intrafusal fibers

Specialized muscle fibers contained within the capsule of a muscle spindle that function as sensory receptors.

Modified Van Gieson method

A staining technique using hematoxylin and picric acid-ponceau stain used to visualize transverse sections of muscle tissue.