What best describes the composition of myocytes in smooth muscle?

The composition of myocytes in smooth muscle is best described as fusiform with no striations. Smooth muscle fibers are distinguished by their unique shape, which is tapering at both ends, resembling a spindle or fusiform structure. This shape allows smooth muscle cells to contract efficiently and enables them to fill various spaces within the body, such as in the walls of hollow organs like the intestines and blood vessels.

Another crucial aspect of smooth muscle myocytes is the absence of striations, which are characteristic of skeletal and cardiac muscle fibers. The lack of these striations in smooth muscle is due to the arrangement of actin and myosin filaments, which do not form the regular pattern seen in striated muscles. Instead, these filaments are arranged more randomly throughout the cell, allowing for a different type of contraction that is typically slower and more sustained.

Understanding these characteristics helps to differentiate smooth muscle from other muscle types and highlights its role in involuntary movements within various organ systems.