Final answer:
Transcription factors are responsible for turning on the muscle-specific genes necessary for skeletal muscle cell specification. These proteins bind to DNA and regulate gene expression, a process crucial during the development of muscle cells from myoblasts.
Step-by-step explanation:
All the muscle-specific genes required for the specification of skeletal muscle cells can be switched ON by the action of transcription factors. Transcription factors are a class of proteins that bind to specific genes on the DNA molecule and regulate their transcription. These factors play a critical role during the development of skeletal muscle cells, as they control the expression of genes necessary for the specialized functions of these cells. Skeletal muscle development occurs as embryonic myoblasts, originating from the mesoderm, fuse together to form long, cylindrical muscle fibers. This fusion allows the formation of multinucleated cells adapted for the production of proteins needed for muscle contraction.