It is responsible for causing body movement. Its contractions are under voluntary control from the conscious centers of the brain. Cardiac muscle is also striated in appearance. Its contractions are considered involuntary because they are not controlled by the conscious portion of the brain. Cardiac muscle tissue is found in the heart, which is responsible for pumping blood throughout the body.
Smooth muscle is smooth in appearance.
Its contractions are also considered involuntary. In general, smooth muscle is responsible for controlling the diameter of vessels and ducts throughout the body. Smooth muscle contractions also help move of various substances through these vessels and ducts. Muscle tissue is composed of muscle cells or fibers, which vary in length, shape and color according the function of the specific muscle. This membrane is called a sarcolemma .