Which muscles are under conscious control, like the biceps?

Which muscles are under conscious control, like the biceps?

• A. Involuntary Muscles
• B. Cardiac Muscles
• C. Voluntary Muscles
• D. Smooth Muscles

Answer: (C)

Moving a part of your body when you decide to is possible because skeletal, or voluntary, muscles are under conscious control. These muscles—like the biceps—attach to bones and contract in response to signals from the brain through the somatic nervous system. When you choose to bend your elbow, motor commands travel to the biceps and cause it to contract, producing the movement you intend. In contrast, the other muscle types work automatically. Smooth muscles line the walls of organs and blood vessels and operate without you thinking about them, guided by the autonomic nervous system. The heart’s cardiac muscle also beats on its own, driven by intrinsic pacemaker activity. So the muscles you actively control are the voluntary (skeletal) muscles.

Moving a part of your body when you decide to is possible because skeletal, or voluntary, muscles are under conscious control. These muscles—like the biceps—attach to bones and contract in response to signals from the brain through the somatic nervous system. When you choose to bend your elbow, motor commands travel to the biceps and cause it to contract, producing the movement you intend.

In contrast, the other muscle types work automatically. Smooth muscles line the walls of organs and blood vessels and operate without you thinking about them, guided by the autonomic nervous system. The heart’s cardiac muscle also beats on its own, driven by intrinsic pacemaker activity. So the muscles you actively control are the voluntary (skeletal) muscles.