Question

human proteins can be produced by cells in the milk-producing mammary glands of transgenic mammals if the regulatory sequence of a milk gene is used to produce the recombinant gene. why is it important to use the regulatory sequence of a milk gene when constructing a recombinant gene used to produce a human protein secreted in milk? the regulatory sequence controls:
the location of gene expression.
the sequence of nucleotides in dna.
the identity of a protein produced.
whether ribosomes recognize mrna.

Explanation:

Regulatory sequences of milk genes are active specifically in mammary gland cells. By linking a human protein-coding gene to this regulatory sequence, the recombinant gene is only expressed in mammary glands, ensuring the protein is secreted in milk. This controls where (which cells/tissue) the gene is expressed. The other options are incorrect: nucleotide sequence is determined by the gene itself, protein identity by the coding sequence, and ribosome recognition of mRNA is related to translation initiation signals, not milk gene regulatory sequences.

Answer:

the location of gene expression.