heart
It is the eyelids!
Ear muscles.
The eyelids
in my opinion eyes and hands
Coordination of muscles is the muscles working together in sync to move a part of the body.
There aren't any antigravity muscles in the human body. But as long as you're upright there are plenty of muscles that are working against gravity.
It depends on the part of the body you are working.
The pectoral muscles are located in the chest area. Strengthening these muscles can help improve the shape, size, and strength of the chest.
Yes, planks can effectively work the chest muscles as they engage the core muscles which support the body in a plank position, indirectly working the chest muscles as well.
When the heart pumps blood around the body it makes more blood available to all parts of the body, including the muscles
The eyes and mouth
Your muscles are the strongest parts of your body, even if you work you muscles to exhaustion, they will not hurt. It takes an awful lot to make your muscles hurt.