Do all muscle cells contain striations?

Not all muscle cells contain striations. Striated muscle, also known as skeletal muscle, has a banded appearance due to the arrangement of actin and myosin filaments. These striations are visible under a microscope and give skeletal muscle its characteristic striped appearance. Smooth muscle, which is found in the walls of internal organs such as the stomach and intestines, does not have striations. Instead, smooth muscle cells have a spindle-shaped appearance and contain actin and myosin filaments that are not arranged in a regular pattern. Cardiac muscle, which is found in the heart, has striations but they are less distinct than those in skeletal muscle. This is because the actin and myosin filaments in cardiac muscle are arranged in a less regular pattern than in skeletal muscle.