Human Anatomy and Physiology - The Muscular System

These flashcards cover key terms and definitions related to the structure and function of the muscular system.

Skeletal Muscle Fibers

Long, thin skeletal muscle cells surrounded by a layer of extracellular matrix called Endomysium.

Fascicle

A bundle of skeletal muscle fibers surrounded by connective tissue known as Perimysium.

Epimysium

A layer of connective tissue that surrounds all the fascicles in a muscle.

Fascia

The most superficial connective tissue sheath that is continuous with the Epimysium.

Voluntary Muscle

Skeletal muscle that is under conscious control and requires stimulation by the nervous system to contract.

Myofascial Trigger Point

A discrete, irritable area within the fascia surrounding a muscle that can cause pain and sustained contraction.

Parallel Muscle

Muscle with evenly spaced fascicles that attach to a tendon of similar width.

Convergent Muscle

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

Circular Muscle

Muscle that encircles a structure and constricts it when contracting, also known as a sphincter.

Pennate Muscle

Muscle where fascicles attach to a tendon at an angle, resembling a feather.

Agonists (Prime Movers)

Muscles providing the most force for a given movement.

Antagonist

Muscle that opposes the action of the agonist and is usually situated on the opposite side of a joint.

Synergists

Muscles that assist the agonist in performing a movement.

Fixators

Muscles that stabilize a bone in place to enhance movement efficiency.

Origin

The fixed attachment point of a muscle.

Insertion

The movable attachment point of a muscle.

First-Class Lever

A lever where the load is on one side, the fulcrum is in the middle, and force is applied on the other side.

Second-Class Lever

A lever with the fulcrum at one end, load in the middle, and force applied on the other end.

Third-Class Lever

A lever where the load is at one end, force is applied in the middle, and the fulcrum is at the opposite end.

Mechanical Advantage

Condition in which lever systems use a small force to move a large load.

Muscle Strain

Injury resulting from excessive stretching or contraction of a muscle, leading to tears.

PRICE Method

Treatment for muscle strains involving Protect, Rest, Ice, Compression, and Elevation.