Chapter 10: Muscle Tissue

These flashcards cover key terms and definitions related to muscle tissue, its types, functions, and related physiological concepts.

Muscle Tissue

Tissue that contracts to produce movement.

Skeletal Muscle

Voluntary, striated muscle that is usually attached to bones.

Cardiac Muscle

Involuntary, striated muscle found in the heart.

Smooth Muscle

Involuntary muscle found in the walls of hollow organs, not striated.

Excitability

The ability of muscle tissue to respond to stimuli.

Contractility

The ability of muscle tissue to shorten and generate force.

Extensibility

The capacity of muscle tissue to be stretched.

Elasticity

The ability of muscle tissue to return to its original shape after being stretched.

Myology

The study of muscles.

Sarcoplasmic Reticulum (SR)

Smooth endoplasmic reticulum in muscle fibers that stores calcium.

Neuromuscular Junction (NMJ)

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

Action Potential

A rapid change in membrane potential that occurs when the muscle is stimulated, leading to contraction.

Acetylcholine (ACh)

A neurotransmitter released at the NMJ that stimulates muscle contraction.

Muscle Fiber (Myofiber)

An individual muscle cell, made up of myofibrils.

Myofilaments

The contractile proteins within muscle fibers; primarily actin (thin) and myosin (thick).

Cross-Bridge Cycle

The process through which myosin heads attach to actin filaments, pulling them to cause muscle contraction.

Tropomyosin

A regulatory protein that blocks the binding sites on actin in a relaxed muscle.

Troponin

A protein that binds calcium ions and moves tropomyosin to expose binding sites on actin.

Isotonic Contraction

A type of muscle contraction where the muscle changes length while maintaining tension.

Isometric Contraction

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

Muscle Tone

The state of partial contraction in muscles, maintaining posture.

Fast-Twitch Fibers

Muscle fibers that are adapted for rapid contractions; fatigue quickly.

Slow-Twitch Fibers

Muscle fibers that are adapted for endurance; resistant to fatigue.

Muscular Dystrophy

A group of hereditary diseases leading to progressive weakness and degeneration of skeletal muscles.

Myasthenia Gravis

An autoimmune disorder characterized by weakness and rapid fatigue of voluntary muscles.