What is the structure of skeletal muscle cells?

Skeletal muscle cells form the muscles that we use to move. They are attached to bones by tendons, which are connective tissues. The tendons are typically about 2 cm to 3 cm in length though sometimes they can be as long as 30 cm. 

Skeletal muscle cells are long and cylindrical in shape. They are striated, with alternating light and dark bands, caused by the special arrangement of proteinaceous myofilaments. Each skeletal muscle cell has more than one nucleus. This multinucleate nature of skeletal muscle cells is because they are formed from the fusion of embryonic myoblasts. These cells also contain many mitochondria, which generate sufficient ATP to meet the cells’ high energy requirements. 

A specialized type of plasma membrane called the sarcolemma reticulum lines every skeletal muscle cell. The sarcolemma reticulum encloses a specialized type of cytoplasm known as sarcoplasm, which contains the endoplasmic reticulum, an oxygen storage site called myoglobin, and several myofibrils, which are tubular protein structures composed of three types of myofilaments. The three types of myofilaments are made up of different types of proteins that work together to generate muscle contractions.