Muscular System Lecture Notes

This set of flashcards covers key terms and concepts related to the muscular system as discussed in the lecture.

Muscle Tissue

One of the four primary tissue types consisting of elongated muscle cells specialized for contraction.

Skeletal Muscle

Type of muscle tissue that is composed of skeletal muscle fibers, connective tissue, nerves, and blood vessels.

Cardiac Muscle

Muscle tissue found only in the heart, characterized by striated and branched cells connected by intercalated discs.

Smooth Muscle

Type of muscle tissue that is spindle-shaped, single-nucleate, and found in the walls of organs.

Epimysium

Connective tissue layer that covers the entire muscle.

Perimysium

Connective tissue that divides muscles into fascicles or bundles of muscle fibers.

Endomysium

Connective tissue that covers each muscle fiber and ties fibers together.

Muscle Fiber

Individual muscle cell; also known as muscle fiber.

Tendon

Bundle of fibers that attaches muscle to bone.

Aponeurosis

Broad sheet of fibers connecting muscles to each other.

Sarcoplasm

Cytoplasm of a muscle fiber, containing organelles and myofibrils.

Myofibrils

Cylinder-shaped structures in muscle fibers made up of thick and thin filaments.

Sarcoplasmic Reticulum

Specialized smooth endoplasmic reticulum that forms a network around each myofibril.

Sarcomeres

Repeating functional units of myofilaments, the smallest functional units of skeletal muscle fiber.

Sliding Filament Theory

Theory explaining muscle contraction through the sliding of thin filaments over thick filaments.

Prime Mover

Muscle that is chiefly responsible for producing a specific movement.

Antagonist

Muscle that opposes the action of another muscle.

Synergist

Muscle that assists the prime mover in performing its action.

Muscle Hypertrophy

Increase in muscle size through exercise and resistance training.

Muscle Atrophy

Decrease in muscle size typically due to lack of use or illness.

Fast-Twitch Fibers

Muscle fibers that are anaerobic, designed for strength, and fatigue easily.

Slow-Twitch Fibers

Muscle fibers that are aerobic, have more endurance, and are resistant to fatigue.