Question

what controls the timing of gene expression?
o nucleotides that dictate the sequence of amino acids in the protein
o transgenic portion of a gene
o coding sequence for a gene
o alleles for a gene
o regulatory sequence for a gene

Explanation:

Gene expression timing is regulated by regulatory sequences. These sequences can turn genes on or off at specific times, controlling when proteins are made. Nucleotides in coding sequences determine amino - acid order, not timing. Transgenic parts, coding sequences, and alleles don't control the timing of gene expression.

Answer:

regulatory sequence for a gene