Muscle tissues are of mesodermal origin and relate to locomotion and other body movements, such as contraction of the organs of the digestive tract, heart and arteries.
The cells of the muscle tissues are elongated and named after muscle fibers or myocytes. In their cytoplasm, they are rich in two types of protein filament: those of actin and those of myosin, responsible for the great capacity of contraction and distension of these cells.
When a muscle is stimulated to contract, the actin filaments slide between the myosin filaments. The cell decreases in size, characterizing the contraction.
Muscle tissue types
There are three types of muscle tissue: skeletal striated, striated heart and smooth. Each has its own characteristics, appropriate to its role in the body.