What must first occur for transcription to begin? mrna moves the code from the nucleus to the ribosome for protein production. a gene is expressed through protein production. rna polymerase attaches to the promoter. a repressor protein must attach to the operator.

The answer is d. when it begins to fall back to the child's hand

The main role of dna in the  cell is the long-term storage of information. it is often compared to a blueprint, since it contains the instructions to construct other components of the  cell, such as  proteins  and rna molecules.the main function of rna is to carry information of amino acid sequence from the genes to where  proteins  are assembled on  ribosomes  in the  cytoplasm. mark brainliest, my work is good.