Final answer:
Skeletal muscles do not have just one nucleus per cell; they have multiple nuclei present on the periphery of each cell. The other characteristics of skeletal muscles include being attached to bone, having striations, and being under voluntary control.
Step-by-step explanation:
The characteristic that is not present in skeletal muscles is having one nucleus per cell. Skeletal muscles are composed of long, cylindrical fibers, and each fiber is multinucleated, which means it has multiple nuclei. The nuclei are present on the periphery of each cell, and this feature is unique to skeletal muscles. The other characteristics of skeletal muscles include being attached to bone, having striations, and being under voluntary or 'willed' control.