Why do you think some muscles are voluntary and other muscles are involuntary

Some of them must work at all times while some work only most, or some of the time.

The skeletal muscle is made of voluntary muscles attached to the skeleton, voluntary muscles are muscles you control by thinking about them, but involuntary muscles aren't controlled my you consciously. Like smooth muscle and cardiac muscle these muscles are in your blood vessels, intestines, stomach, urinary bladder, and heart. You cannot control these muscles because they are automatic and regulate your bodily functions. Hope my answer assisted you!

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