Q.Distinguish between smooth muscles and skeletal muscles.

Step 1. Number of nuclei: skeletal muscle fibres are syncytial (multinucleate), with several nuclei pushed to the periphery of the fibre; smooth muscle cells are uninucleate, with a single nucleus at the centre.

Step 2. Cell shape: skeletal muscle fibres are long, cylindrical myofibres bundled into fasciculi; smooth muscle cells are individually spindle-shaped (fusiform) and unbranched, arranged as sheets or layers.

Step 3. Striations: skeletal muscle shows a striated (banded) appearance, from its sarcomeres' alternating A bands and I bands; smooth muscle shows no striations, since its actin/myosin filaments are not organised into the same repeating sarcomere pattern.

Step 4. Actin/myosin proportion: smooth muscle contains less myosin and more actin relative to skeletal muscle. …

Compare the two muscle types point by point — nuclei, cell shape, striation, actin/myosin ratio, voluntary contr …

• Forgetting that skeletal muscle fibres are multinucleate while smooth muscle cells are uninucleate — a commonly reversed detail. …