Muscle Contraction & Relaxation

Front

What slides inward during muscle contraction?

Back

Actin

Front

What are the thin filaments in muscle fibers?

Back

Actin

Front

After calcium is released from the sarcoplasmic reticulum, it binds to which protein?

Back

Troponin

Front

How is calcium (Ca2+) moved back into the sarcoplasmic reticulum?

Back

Active transport

Front

What ions are essential for initiating muscle contraction?

Back

Calcium ions

Front

What is the role of troponin in muscle contraction?

Back

Troponin binds calcium ions, causing a conformational change that allows muscle contraction to occur.

Front

What is the function of the sarcoplasmic reticulum in muscle cells?

Back

The sarcoplasmic reticulum stores and releases calcium ions, which are crucial for muscle contraction.

Front

What is the difference between actin and myosin in muscle contraction?

Back

Actin is a thin filament that slides inward during contraction, while myosin is a thick filament that pulls on actin.

Front

What is the process called when muscle fibers shorten during contraction?

Back

Sliding filament theory.

Front

What triggers the release of calcium ions from the sarcoplasmic reticulum?

Back

An action potential in the muscle cell.