Muscle Contraction and Sarcomere Function

Flashcards covering key vocabulary related to muscle contraction and sarcomere structure.

Sarcomere

The structural unit of a myofibril in a muscle, consisting of actin and myosin filaments.

Myosin thick filament

A filament composed of myosin molecules, involved in muscle contraction.

Actin thin filament

A filament made of actin proteins that interact with myosin during muscle contraction.

Z-disc

The boundary structure of a sarcomere where actin filaments are anchored.

Cross bridge cycle

The series of biochemical events that occur when myosin heads bind to actin, causing muscle contraction.

Calcium

An essential ion required for muscle contraction; it binds to troponin, enabling actin-myosin interaction.

ATP (Adenosine Triphosphate)

The energy currency of the cell; necessary for muscle contraction and relaxation.

Power stroke

The action of myosin pulling on actin during contraction, powered by ATP hydrolysis.

ATP hydrolysis

The conversion of ATP to ADP and phosphate, providing energy for muscle contraction.