structure of muscles

Epimysium

Connective tissue that wraps around the whole muscle, separating it from other tissues in the body.

Perimysium

Connective tissue that divides the muscle into bundles called fascicles, allowing them to work as individual units.

Endomysium

Connective tissue that wraps around each individual muscle fiber within a fascicle.

Muscle Fibers

Cells within muscles, also known as muscle cells, that can be recruited independently during contraction.

Sarcolemma

Membrane surrounding muscle fibers.

Sarcoplasm and Sarcoplasmic Reticulum

Contains the calcium needed for muscle contraction.

Myofibrils

Long cylindrical structures made of protein within muscle fibers.

Sarcomeres

Units within myofibrils made up of myofilaments of two types - thick (myosin) and thin (actin).

Actin and Myosin

Types of myofilaments that slide over each other during contraction, creating a banded appearance.

Fascicles

Bundles of muscle fibers within skeletal muscles, containing myofilaments of actin and myosin.