Muscular System I - BIO-110

Vocabulary flashcards covering key terms and concepts related to the muscular system.

Skeletal Muscle

Type of muscle attached to the bones, under voluntary control.

Cardiac Muscle

Involuntary muscle that makes up the heart and is responsible for pumping blood.

Smooth Muscle

Involuntary muscle found in the walls of internal organs, like the digestive tract.

Fascia

A thin covering of connective tissue surrounding a muscle.

Tendon

Cord-like mass of connective tissue that connects muscle to bone.

Aponeurosis

Sheet-like mass of connective tissue connecting muscle to bone, skin, or another muscle.

Epimysium

Connective tissue that surrounds the whole muscle and lies beneath the fascia.

Perimysium

Connective tissue that surrounds fascicles (bundles of muscle fibers) within a muscle.

Endomysium

Connective tissue that surrounds individual muscle fibers within a fascicle.

Sarcoplasmic Reticulum (SR)

Endoplasmic reticulum of muscle cells, responsible for storing calcium.

Neuromuscular Junction (NMJ)

Synapse where a motor neuron meets a skeletal muscle fiber.

Acetylcholine (ACh)

Neurotransmitter that stimulates muscle contraction.

Excitation-Contraction Coupling

The process of converting a muscle fiber stimulus into contraction.

Sliding Filament Model

Describes how muscle contraction occurs through the sliding of thin and thick filaments.

Cross-Bridge Cycling

The sequence of events in which myosin heads bind to actin and pull, resulting in muscle contraction.

Muscle Fatigue

Inability to contract a muscle, often due to decreased blood flow or lactic acid accumulation.

Threshold Stimulus

Minimum strength of stimulation needed to trigger a muscle contraction.

Isotonic Contraction

Muscle contraction that results in a change in muscle length while lifting a load.

Isometric Contraction

Muscle contraction that does not change muscle length despite tension generation.