The different types of cells in a body contain identical sets of dna molecules. however, the structures and functions of the cell types vary widely. gene expression describes the way in which genetic information is put into action in undifferentiated stem cells, making some cells, skin cells and others, muscle fibers. dna is first transcribed into mrna. the codons on the mrna specify the order in which amino acids are placed to form a protein. proteins, then play an important role in expressing an organism's physical traits. which of these factors does not play a significant role in cell differentiation? a) transcription factors bind to regulatory regions of a gene and affect their expression by turning genes off or on. b) certain segments of dna will be lost in the translation process, rendering certain genes obsolete in particular cells. c) certain genes can be turned on or off by the presence of concentration of transcription factors in the cytoplasm of the cell. d) the type and amount of rna may determine how a cell differentiates. the process of rna interference can even shut down targeted genes, affecting cell differentiation.