Muscle Contractions Review

Front

What is necessary for the myosin to release the actin?

Back

ATP is required for myosin to release actin during muscle contraction.

Front

What substance unblocks the actin?

Back

Calcium ions are necessary to unblock actin, allowing muscle contraction to occur.

Front

Which myofilament is thick and dark?

Back

Myosin is the thick and dark myofilament responsible for muscle contraction.

Front

Do myosin and actin physically interact when muscle is resting?

Back

False. Myosin and actin do not interact when the muscle is at rest.

Front

What structure connects the message from the brain to a muscle?

Back

The motor neuron transmits signals from the brain to the muscle.

Front

What is the role of ATP in muscle contraction?

Back

ATP provides the energy required for myosin to detach from actin and for muscle contraction to continue.

Front

What is the function of calcium ions in muscle contraction?

Back

Calcium ions bind to troponin, causing a conformational change that exposes binding sites on actin.

Front

What are the two main types of muscle fibers?

Back

The two main types of muscle fibers are slow-twitch (Type I) and fast-twitch (Type II) fibers.

Front

What is a sarcomere?

Back

A sarcomere is the basic contractile unit of muscle tissue, defined by the area between two Z lines.

Front

What is the sliding filament theory?

Back

The sliding filament theory explains how muscles contract by the sliding of actin and myosin filaments past each other.