Muscle Contraction

Flashcards covering key concepts and definitions from the lecture on muscle contraction.

Muscle fibers

The basic unit of skeletal muscle, each muscle fiber is a cell that contains multiple nuclei.

Skeletal muscles

Muscles that are connected to bones and are involved in body movement, typically working in opposition.

Neuromuscular junction

The synapse or junction between a motor neuron and a muscle fiber, where nerve signals stimulate muscle contraction.

Sarcomeres

The repeating units within myofibrils made of actin and myosin filaments, essential for muscle contraction.

Actin

Thin filaments found in the sarcomeres of muscle fibers that interact with myosin for muscle contraction.

Myosin

Thick filaments found in the sarcomeres of muscle fibers that interact with actin during muscle contraction.

Fast twitch muscle fibers

Muscle fibers that contract rapidly but have less endurance and rely on anaerobic metabolism.

Slow twitch muscle fibers

Muscle fibers that contract slower, have greater endurance, and use aerobic respiration due to denser capillary beds.

ATP (Adenosine Triphosphate)

The energy molecule used by muscle cells to break the link between actin and myosin and facilitate muscle contraction.

Muscle twitch

The duration between contraction and relaxation of a muscle.