What are muscle cells?

Muscle cells are cells in the body that are adapted for movement by contracting and relaxing. There are three main types of muscle cells – skeletal, smooth, and cardiac muscles. Although each of these are unique in design and in the way they contract, the primary function of all is to support movement. 

1. Skeletal muscles are striated with alternating dark and light bands and multinucleated. They are attached to the skeleton and responsible for voluntary movements of the body.   
2. Smooth muscles are spindle-shaped, non-striated and uninucleate. They are controlled by the autonomic nervous system and regulate all involuntary movements in the body. Smooth muscles stimulate the contractility of the blood vessels and airways as well as the reproductive, digestive, and urinary systems. 
3. Cardiac muscles are a type of uninucleate involuntary muscle found only in the heart. They facilitate the pumping of blood by rhythmically contracting and expanding the walls of the heart.