Muscular System Notes 2023 part 1

Front

What must happen before muscle fibers can contract?

Back

Calcium ions must change the shape of actin, ATP provides energy to form cross bridges between actin and myosin, sodium ions must stimulate the release of calcium ions. All of these must happen before contraction can take place.

Front

What is the first step in muscle contraction?

Back

Acetylcholine is released and sodium enters.

Front

What type of muscle tissue is responsible for voluntary movements?

Back

Skeletal muscle.

Front

What is the thin filament that makes up muscle?

Back

Actin.

Front

What role does acetylcholine play in muscle contraction?

Back

It causes an action potential to begin in muscle fibers.

Front

What is the function of myosin in muscle contraction?

Back

Myosin forms cross bridges with actin to facilitate muscle contraction.

Front

What is the role of calcium ions in muscle contraction?

Back

Calcium ions change the shape of actin, allowing myosin to bind and contract the muscle.

Front

What is the difference between skeletal, cardiac, and smooth muscle?

Back

Skeletal muscle is voluntary and striated, cardiac muscle is involuntary and striated, and smooth muscle is involuntary and non-striated.

Front

What is ATP and why is it important for muscle contraction?

Back

ATP provides the energy required for muscle contraction and relaxation.

Front

What happens during muscle fatigue?

Back

Muscle fatigue occurs when there is a depletion of ATP and accumulation of lactic acid.