Final answer:
Skeletal muscle fibers are voluntary, multinucleated, and striated cells. They are usually attached to bone and under voluntary control.
Step-by-step explanation:
Skeletal muscle fibers are the cells of skeletal muscle. This type of cell is voluntary, multinucleated, and striated. Skeletal muscle is usually attached to bone and is under voluntary control. Each muscle cell, or fiber, contains multiple nuclei and has a striped appearance due to the arrangement of contractile proteins actin and myosin.