Muscular System Histology And Physiology

Flashcards covering key vocabulary terms and definitions related to the muscular system histology and physiology.

Skeletal Muscle

Muscle responsible for voluntary movements, attached to bones, striated, and with multiple nuclei.

Smooth Muscle

Involuntary muscle found in the walls of hollow organs, not striated, single centrally located nucleus.

Cardiac Muscle

Involuntary muscle found in the heart, striated, single centrally located nucleus, autorhythmic.

Hypertrophy

Increase in the size of muscle fibers, leading to larger muscles.

Muscle Twitch

The response of a muscle fiber to a single action potential, including lag, contraction, and relaxation phases.

Excitation-Contraction Coupling

The physiological process of converting an electrical stimulus to a mechanical response in muscle fibers.

Cross-Bridge Cycle

The process in muscle contraction where myosin heads bind to actin, pull, release, and return to original position.

Resting Membrane Potential

The voltage difference across the plasma membrane of a muscle fiber when it is not being stimulated.

Myofilaments

The contractile proteins within muscle fibers, including actin (thin) and myosin (thick) filaments.

Isometric Contraction

Muscle contraction that does not change length but increases tension.

Isotonic Contraction

Muscle contraction that changes length while maintaining constant tension.

Motor Unit

A motor neuron and all the muscle fibers it innervates; responsible for muscle contraction.

Treppe

The staircase effect wherein muscle contractions become progressively stronger with repeated stimulus.

Wave Summation

Increased tension produced in muscle fibers when stimuli are applied in quick succession.

Action Potential

A rapid change in the membrane potential of a muscle fiber that initiates contraction.

Neuromuscular Junction

The synapse or junction between a motor neuron and a muscle fiber where impulses are transmitted.

ATP Sources for Muscle Contraction

ATP is produced from creatine phosphate, anaerobic respiration, and aerobic respiration.

Oxygen Deficit

The shortfall of oxygen resulting from intense exercise; requires more oxygen for recovery.

Rigor Mortis

The stiffening of muscles after death due to calcium ions leaking into muscles and forming cross-bridges.