These are about 8 nm in diameter and, being the thinnest of the cytoskeletal filaments, are also called microfilaments. (In skeletal muscle fibers they are called thin filaments.) Some functions of actin filaments: 1  form a band just beneath the plasma membrane that.  provides mechanical strength to the cell.
The microfilaments are arranged so that the fibers appear to have stripes (striations) in them. These are also called voluntary muscles.. Smooth muscle is involuntary, and is not under conscious control; the muscles in your digestive system are smooth muscles.The cells are individual and are found in sheets instead of long fibers. (Cardiac muscle has characteristics of both, but are not referred to in the question).here skeletal muscle is voluntary, cardiac muscle is autorhythmic (beats involuntarily; generates its own action potentials). 3. Smooth muscle: refers to the muscles that are controlled involuntarily by the brain, like those attached to the base of hair follicles or in the walls of the gastro-intestinal tract.
Involuntary Muscles. Involuntary muscles are the muscle that cannot be controlled consciously. Their actions are mainly controlled by the autonomic nervous system in the body. Main types of involuntary muscles are smooth muscles and cardiac muscles.