Muscle Types and Movement Control

Flashcards covering muscle types, movement control, proprioception, and related homeostatic imbalances.

Smooth Muscle

Narrow, tapered, rod-shaped cells that are nonstriated and nonucleated, found in the walls of internal organs and blood vessels, controlled involuntarily.

Cardiac Muscle

Striated, tubular, branched, uninucleated fibers that occur in the walls of the heart, functioning under involuntary control.

Skeletal Muscle

Striated, tubular, multinucleated fibers attached to the skeleton that allow for voluntary movement.

Flexion

The action of closing a joint, involving the flexor muscles.

Extension

The action of opening or extending a joint, involving the extensor muscles.

Lower Motor Neuron

Neurons with cell bodies in the ventral spinal cord that send axons to muscles, responsible for muscle contraction.

Motor Unit

A lower motor neuron and all the muscle fibers it innervates.

Proprioception

The body's ability to sense its position and movement, involving feedback to contract muscles.

Spinal Interneurons

Inhibitory neurons that send signals to antagonist muscles to prevent them from opposing the target muscle.

Muscle Spindles

Sensory receptors within muscle fibers that sense muscle contraction and provide feedback to the brain.

Gamma Motor Neuron

Neurons that maintain the contraction of muscle fibers wrapped by muscle spindles, ensuring accurate sensory feedback.

Golgi Tendon Organs

Receptors located between tendons and muscles that provide feedback on muscle tension and activity, preventing over contraction.

ALS

A disease affecting lower motor neurons, hindering signal transduction from the brain to muscles.

Bell's Palsy

A condition causing weakness or loss of motor control on one side of the face, usually due to cranial nerve pressure.