Musculoskeletal System: Joints and Muscles

Vocabulary flashcards detailing key concepts related to joints and muscle anatomy and physiology.

Fibrous Joint

A joint type with no cavity and mostly immobile, examples include sutures, gomphoses, and syndesmoses.

Cartilaginous Joint

A joint type with no cavity that allows slight movement, including synchondroses and symphyses.

Synovial Joint

A joint type with a cavity that is freely movable, examples include hinge, pivot, and ball-and-socket joints.

Synarthrosis

A functional joint type that is immovable, such as the skull sutures.

Amphiarthrosis

A functional joint type that is slightly movable, like the pubic symphysis.

Diarthrosis

A functional joint type that is freely movable, such as the shoulder or knee.

Articular Cartilage

Covers the ends of bones in synovial joints and provides cushioning.

Synovial Fluid

A lubricating fluid found in synovial joints that reduces friction and nourishes cartilage.

Bursae

Fluid-filled sacs that cushion and reduce friction in synovial joints.

Flexion

A type of angular movement that decreases the angle between body parts.

Extension

An angular movement that increases the angle between body parts.

Muscle Fiber Type I

Also known as slow oxidative, it is resistant to fatigue and suited for endurance activities.

Muscle Fiber Type IIx

Fast glycolytic fibers that fatigue quickly and are suited for short bursts of activity.

Muscle Fiber Type IIa

Fast oxidative-glycolytic fibers that provide a balance of endurance and power.

Motor Unit

A motor neuron and all the muscle fibers it innervates.

Agonist (Prime Mover)

The primary muscle responsible for a specific movement.

Antagonist

A muscle that opposes the action of the agonist.

Synergist

A muscle that assists the agonist in performing an action.

Fixator

A muscle that stabilizes the origin of the agonist.

Origin (of muscle)

The less moveable attachment of a muscle.

Insertion (of muscle)

The more moveable attachment of a muscle.

ATP Sources for Muscle Contraction

Aerobic metabolism is the most efficient source of ATP for muscle contraction.

Isotonic Contraction

A muscle contraction where the muscle changes length while the tension remains the same.

Isometric Contraction

A muscle contraction where the muscle generates tension without changing length.

Neuromuscular Junction (NMJ)

The synapse or junction between a motor neuron and a muscle fiber.