"""smooth muscle fibres, sem"" - microbiology stock videos & royalty-free footage"
{"Image ImageDescription": "\"Smooth muscle. Animated coloured scanning electron micrograph (SEM) of smooth muscle from the trachea (windpipe). Smooth muscle is not under voluntary control, unlike skeletal (striated) muscle. Smooth muscle comprises bundles of muscle fibres (brown). These contain the contractile proteins actin and myosin, which slide over each other to contract the muscle.\""}