In what way is the appearance of cardiac muscle similar to that skeletal muscle?

They are both muscles of the muscular system of the body, in their appearance they are both composed of muscle tissues that have different functions as cardiac is for the heart and a type of muscle that is activated by the autonomic nervous system while the skeletal muscle is a muscle for voluntary movement and is connected with the skeletal system or bones.

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A human body is composed of muscles. Without it, the human body cannot function and will die. 

There are three types of muscle tissues: Skeletal muscle, Cardiac muscle, and Smooth muscle.

The skeletal muscle aids in the movement of the human skeleton. The 600 skeletal muscles make up 40 % of our body weight and are reliant on the signals released by our nervous system to start moving.

Cardiac muscles are those muscles which encloses our hearts. They are involuntary muscles which pumps blood throughout our bodies by creating steady and rythmic pulsing. They also make our heart contract by producing electrical impulses. 

Smooth muscles are found in the walls of blood vessels, respiratory passageways, and hollow organs. Its contracting movement is wavelike and it helps in the transfer of food through our stomachs or urine through our bladder. 

These muscles responds to nerve impulses and other stimuli.