skeletilihas

Skeletilihas, also known as striated muscle or voluntary muscle, is one of the three types of muscle tissue in the human body, alongside cardiac muscle and smooth muscle. Its primary function is to facilitate movement of the skeleton, which is why it is called skeletal muscle. These muscles are attached to bones by tendons, and when they contract, they pull on the bones, causing the body to move.

Skeletal muscle tissue is characterized by its striated appearance, meaning it has a striped or banded pattern when viewed under a microscope. This striation is due to the organized arrangement of contractile proteins, actin and myosin, within the muscle fibers. Unlike cardiac and smooth muscle, skeletal muscle is under voluntary control, meaning we consciously decide when to move our muscles.

Each skeletal muscle is composed of numerous muscle fibers, which are long, cylindrical cells. These fibers contain multiple nuclei and are packed with myofibrils, the basic contractile units of the muscle cell. The contraction of skeletal muscle is initiated by nerve impulses from motor neurons. These impulses trigger a series of chemical events that cause the actin and myosin filaments to slide past each other, resulting in muscle shortening and thus, movement.

Skeletal muscles are crucial for a wide range of activities, from gross motor movements like walking and running to fine motor skills such as writing and playing a musical instrument. They also play a role in maintaining posture and generating heat. The strength and endurance of skeletal muscles can be improved through exercise and training.