Muscular System

These flashcards cover key vocabulary and concepts from the lecture on the Muscular System, ideal for quick review and study.

Skeletal Muscle Fibers

Long, thin shape cells that make up skeletal muscles.

Endomysium

Thin layer of extracellular matrix surrounding each skeletal muscle fiber.

Fascicle

A bundle of 10 to 100 muscle fibers surrounded by perimysium.

Perimysium

Connective tissue surrounding a fascicle.

Epimysium

Outer layer of connective tissue surrounding the entire muscle.

Fascia

Most superficial connective tissue sheath continuous with epimysium.

Tendons

Connect muscle to bone or other structures they move.

Voluntary

Skeletal muscle that is under conscious control.

Myofascial Trigger Point

A discrete, irritable point in the fascia surrounding a muscle, causing pain.

Muscle Knots

Another term for myofascial trigger points.

Parallel Muscle

Muscle with evenly spaced fascicles attaching to a tendon that is about the same width.

Convergent Muscle

Muscle that is broad at one end and uniformly tapers to a single tendon.

Circular Muscle

Muscle that encircles a structure, such as the opening to the eye, to control its closure.

Fusiform Muscle

Muscle that is thicker in the middle and tapered at both ends.

Pennate Muscle

Muscle with fibers that attach to a tendon at an angle.

Agonists

Muscles that provide most of the force required for a given movement.

Antagonists

Muscles that oppose the action of agonists.

Synergists

Muscles that assist the agonists in performing a movement.

Fixators

Muscles that stabilize a joint to allow other movements.

Origin (O)

Fixed attachment of a muscle.

Insertion (I)

Attachment of the muscle that moves.

Lever System

A system consisting of bones, load, force, and fulcrum used in body movements.

Mechanical Advantage

Using a small force to move a large load.

Mechanical Disadvantage

Requiring a greater force to move a load.

Muscle Strain

Injury resulting from excessive stretching or contraction force.

Kegel Exercises

Pelvic floor exercises to strengthen the muscles and treat urinary incontinence.

Extrinsic Eye Muscles

Six muscles that allow movement of the eyes.

Muscles of Facial Expression

Muscles that insert into skin or connective tissue to change the shape of the face.

Diaphragm

Dome-shaped muscle separating thoracic and abdominal cavities, aids in breathing.

Internal Intercostal Muscles

Muscles that assist in forced expiration.

Tibialis Anterior

Main dorsiflexor of the foot.

Gastrocnemius Muscle

Powerful calf muscle that assists in plantarflexion.

Intrinsic Foot Muscles

Muscles that support the arches of the foot and allow skilled movements.