If what you mean is; what muscles are found in organs, then the answer is smooth muscle.
Smooth muscle is an involuntary kind of muscle, in other words, you are unable to control it consciously. Smooth muscle generally lines the lumen of ducts and arteries. In arteries, this means that blood pressure can be maintained throughout the body. In ducts, they act like someone squeezing an old tube of toothpaste to try and get the last bit out.
There is also a particular kind of muscle called cardiac muscle, which is found in the heart. This kind of muscle contracts to a 'beat' set by the sino-atrial node (SAN) in order to force blood out of the atria and ventricles into the aorta.
The shoulder belongs to the musculoskeletal system, which comprises bones, muscles, tendons, and ligaments that provide structure, support, and movement to the body. Specifically, the shoulder involves the bones of the shoulder girdle, muscles that facilitate arm movement, and ligaments that stabilize the joint. This system works in conjunction with the nervous system to control and coordinate movements.
The muscular system is responsible for actually moving the arm up, while the nervous system coordinates the activation of the muscles to raise the arm in response to your conscious thought or instruction from the brain.
Skeletal system
Skeletal system
the arm
The nervous system sends signals to the muscles, allowing the skeletal system to move the arm and hand to pick up the pencil. The muscular system contracts and relaxes to control the movement, while the skeletal system provides structure and support for the muscles to work.
The triceps belong to the muscular system, specifically as part of the skeletal muscle group. This muscle is located at the back of the upper arm and is responsible for extending the elbow joint. Additionally, the triceps play a role in movements involving the shoulder, contributing to various physical activities.
They belong to the peripheral nervous system, as opposed to the central nervous system (as they are to be found on the periphery of the body).
They belong to the peripheral nervous system, as opposed to the central nervous system (as they are to be found on the periphery of the body).
Skeletal muscles in the arm
While basically any organ in your body has a function (aside perhaps of the appendix) the only "organ" in your arm that you could have removed without losing arm functions would be a lymphic node, which is part of your immune system. Losing one of these nodes would lower the effectiveness of your immune system, but not cost you arm function.
The muscles of the arm are natural tighteners to the skin of the arm