General Anatomy: Muscles

Cruciate muscles, like sternocleidomastoid, have fibers crossing each other.

Bipennate muscles, like rectus femoris, have fibers arranged on both sides of a central tendon.

The deltoid muscle has multiple pennate arrangements, making it powerful.

The temporalis muscle has a triangular fascicular arrangement.

Fast fibers rely on glycogen and glycolysis for quick, powerful contractions.

Type I fibers are rich in myoglobin and mitochondria, making them resistant to fatigue.

The endomysium is the connective tissue that surrounds individual muscle fibers.

The Z disc is a dark line in the middle of an I band and marks the boundary of a sarcomere.

A bands are the dark bands in a myofibril, consisting of thick myosin filaments.

A sarcomere is the basic unit of muscle contraction, consisting of actin and myosin filaments.

Tendons are fibrous, non-contractile structures that connect muscles to bones.

The belly of the muscle is the contractile part that generates movement.

The three types of muscle are skeletal, smooth, and cardiac. Connective tissue provides support but is not a type of muscle.

Muscles are contractile tissues that generate movement and are considered the motors of the body.