Biology · Structural Organisation in Animals · NEET
Skeletal muscle is voluntary. You can start and stop its movement whenever you want, for example when you lift your arm or walk. This is because it is controlled by the somatic nervous system. Smooth and cardiac muscles are involuntary. NEET often mixes these up, so remember: only skeletal muscle is voluntary.
Under a microscope, skeletal muscle shows alternate dark and light bands across the fibre. These bands are called striations, so the muscle is called striated (or striped) muscle. The striations come from the ordered arrangement of actin and myosin proteins inside. Cardiac muscle also has faint striations, but skeletal muscle striations are the most clear.
In skeletal muscle the many nuclei lie at the edge of the fibre (peripheral). This is a favourite NEET point. Compare: smooth muscle has one central nucleus, and cardiac muscle has central nuclei. So peripheral + multinucleate = skeletal muscle.
A skeletal muscle fibre is not a single normal cell. During development, many cells fuse together to form one long fibre, so all their nuclei stay inside one fibre. This is why it is called multinucleate and is also described as a syncytium. That is why the fibre can be very long.
Skeletal muscle fibres are unbranched. They run as long, straight cylinders lying side by side. Only cardiac muscle is branched. So if a diagram shows branched fibres with intercalated discs, it is cardiac, not skeletal.
Skeletal muscle is attached to bones of the skeleton, mostly through tendons. Examples for NEET are the biceps and triceps of the arm, and the muscles of the legs. Because it moves the skeleton, it is called skeletal muscle, and its main job is body movement and posture.
Three types of muscles are given as a, b and c. Identify the correct matching pair along with their location in the human body.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Skeletal muscle is the muscle attached to your bones that you move on your own will, like the muscles in your arms and legs. It has long, striped fibres and helps in body movement and posture.
Because under a microscope it shows regular dark and light bands (striations) across each fibre. These bands come from the neat arrangement of actin and myosin proteins.
It is long, cylindrical, unbranched, striated, and multinucleate with the nuclei placed at the periphery. It is a voluntary muscle attached to bone.
Skeletal muscle is unbranched, voluntary, has peripheral nuclei, and no intercalated discs. Cardiac muscle is branched, involuntary, has central nuclei, and has intercalated discs, and is found only in the heart.
The biceps and triceps of the arm, and the muscles of the legs. In the 2024 NEET question, skeletal muscle was matched with the triceps.
