Connective tissue coverings

Tendon

This connective tissue surrounds each muscle and may project beyond the ends of its muscle fibers, forming a cordlike tendon.

Myofibrils

The sarcoplasm also has abundant long, parallel structures called myofibrils.

fasicles

This section contains bundles of skeletal muscle fibers

sarcoplasmasmic

cytoplasm (sarcoplasm) of the fiber contains many small, oval nuclei and mitochondria.

Sarcolemma

Just beneath the muscle cell membrane (sarcolemma)

fascia

An individual muscle is separated from adjacent muscles and held in position by layers of dense connective tissue called fascia.

perimysium

Another layer of connective tissue, called the perimysium, extends inward from the epimysium and separates the muscle tissue into small sections.

skeletal muscle fiber

A skeletal muscle fiber a single muscle cell. Each fiber forms from many undifferentiated cells that fuse during development. The resulting multinucleated muscle fiber is a thin, elongated cyllinder with rounded ends that attach to the connective tissues associated with a muscle.

endomysium

Each muscle fiber within a fasicle lies within a layer of connective tissue in the form of a thin covering called endomysium.

Aponeuroses

Fibers in a tendon may intertwine with those in the periosteum of a bone, attaching the muscle to the bone. Or, the connective tissues associated with a muscle form broad, fibrous sheets called aponeuroses, which may attach to bone or the coverings of adjacent muscles.

epimysium

The layer of connective tissue that closely surrounds a skeletal muscle is called the epimysium, which in some areas of the body may merge with the surrounding deep fascia.

The myofibrils contain

The myofibrils play a fundamental role in the muscle contraction mechanism. They consist of two types of protein filaments: thick filaments composed of the protein myosin, and thin filaments composed primarily of the protein actin.