Parts of Nervous System. Nervous System: Nervous system is the chief controlling and coordinating system of the body. It controls and regulates all activities of the body, whether voluntary or involuntary, and adjusts the individual (organism) to the given surroundings.
Compared to skeletal muscle, smooth-muscle cells are small. They are spindle-shaped, about 50 to 200 microns long and only 2 to 10 microns in diameter. They have no striations or sarcomeres. Instead, they have bundles of thin and thick filaments (as opposed to well-developed bands) that correspond to myofibrils.
Quick Answer. The structure of muscle tissue varies depending upon whether the muscle controls voluntary or involuntary movements, according to the National Cancer Institute. There are three types of muscle: skeletal, smooth and cardiac. Skeletal muscle is striated, smooth muscle is non-striated and cardiac muscle has characteristics of both.