Human Anatomy: Muscles of the Body

This set of flashcards encompasses key concepts, terms, and definitions found in Chapter 11 of the Human Anatomy course on the muscles of the body.

Fascicle Arrangement

The pattern in which muscle fibers are organized within a muscle, influencing its action.

Circular fascicles

Fascicles arranged in concentric rings, often surrounding body openings; main example is sphincter muscles.

Pennate Fascicles

Fascicles that insert into a tendon at an angle; can be unipennate, bipennate, or multipennate.

Mechanical Advantage

Occurs when the effort arm of a lever is longer than the load arm, allowing a smaller effort to move a larger load.

First-class Lever

A lever where the fulcrum is located between the load and the effort, such as in seesaws.

Prime Mover (Agonist)

A muscle that has the primary responsibility for a specific movement.

Synergist

A muscle that assists a prime mover in performing an action, often by stabilizing the movement.

Antagonist

A muscle that opposes or reverses a movement produced by another muscle.

Erector Spinae

A group of deep back muscles that maintain spine curvature and extend the trunk.

Diaphragm

The primary muscle of respiration that flattens upon contraction to increase thoracic cavity volume.

Flexor Muscles

Muscles located in the anterior compartment of the forearm that flex the wrist and fingers.

Intrinsic Muscles of the Hand

Muscles located within the hand that control fine finger movements, including abduction and opposition.

Quadriceps Femoris

A group of muscles on the anterior thigh responsible for knee extension, consisting of four heads.

Hamstrings

A group of posterior thigh muscles responsible for thigh extension and knee flexion.

Skeletal muscles

Muscle tissue attached to bones that facilitate movement through contraction.

Muscle Compartment

Grouping of muscles within a limb that share similar actions and are innervated by the same nerve.

Palpation

The process of feeling internal structures through the skin for assessment and diagnosis.

Suprahyoid Muscles

Muscles located above the hyoid bone that assist in swallowing.

Infrahyoid Muscles

Muscles located below the hyoid bone that act to stabilize the hyoid and aid in swallowing.

Gluteal Region Muscles

Muscles originating from the pelvis and responsible for movement of the hip joint.

Intrinsic Foot Muscles

Muscles responsible for toe movements and supporting the arches of the foot.

Tendons

Cord-like structures that connect muscles to bones, facilitating movement.

Thenar Muscles

Muscles located at the base of the thumb that control its movements.