Muscular System: Histology and Physiology

Flashcards covering key concepts of the muscular system's histology and physiology.

Skeletal Muscle

Muscle attached to bones that enables locomotion, maintains posture, and performs body movements. Striated and voluntary.

Smooth Muscle

Muscle found in the walls of hollow organs that is involuntary and non-striated, responsible for movements such as propelling urine and mixing food.

Cardiac Muscle

Muscle found only in the heart, striated and involuntary, responsible for pumping blood and contains intercalated discs.

Excitation-Contraction Coupling

Mechanism where an action potential leads to muscle fiber contraction, involving sarcolemma, T tubules, and calcium ions.

Neuromuscular Junction

The synapse between a motor neuron and a muscle fiber that transmits signals for muscle contraction.

Motor Unit

A single motor neuron and all the muscle fibers it innervates, affecting muscle control and response to stimuli.

Action Potential

A rapid change in membrane potential that propagates along the plasma membrane, causing muscle contraction.

Treppe

Gradual increase in muscle tension with successive stimuli; each contraction becomes stronger until it stabilizes.

Isometric Contraction

Muscle contraction where length does not change but tension increases, commonly seen in postural muscles.

Isotonic Contraction

Muscle contraction where the muscle changes length while maintaining constant tension, can be concentric or eccentric.