Final answer:
Smooth muscle cells are small, spindle-shaped cells with a single nucleus that can contract over a wide range of lengths. Skeletal muscle cells are long, tubular, striated with multiple nuclei, and much larger in diameter and length. Cardiac muscle cells are also striated but shorter and have a smaller diameter compared to skeletal muscle cells.
Step-by-step explanation:
Smooth muscle cells have a spindle-shaped structure and are considerably smaller in diameter and length when compared to the long, cylindrical skeletal muscle cells. Smooth muscle cells range from about 30 to 200 µm in length, which is thousands of times shorter than skeletal muscle fibers. Additionally, smooth muscle cells have a single nucleus and can contract over a wider range of resting lengths than skeletal and cardiac muscles due to their ability to maintain their contractile function even when stretched.
On the other hand, skeletal muscle cells are long tubular cells that have multiple nuclei and are striated due to their organized sarcomeres containing myofilaments and fibrils. These cells tend to be much larger, both in terms of diameter and length. Cardiac muscle cells, or cardiomyocytes, while also striated with a similar arrangement of contractile elements to skeletal muscle, are much shorter and have smaller diameters in comparison. Unlike smooth muscle cells, both skeletal and cardiac muscle cells have a more organized structure, with skeletal muscle cells featuring multiple nuclei and cardiomyocytes often having a single central nucleus, potentially more in some cells.