Question

when mrna leaves the nucleus, it ____. enters a mitochondria binds to a ribosome fuses with the plasma or cell membrane rewatch

Explanation:

mRNA (messenger - RNA) is involved in protein synthesis. After leaving the nucleus where it is transcribed from DNA, it travels to the ribosomes in the cytoplasm. Ribosomes are the sites of protein synthesis where the mRNA sequence is translated into a polypeptide chain. mRNA does not enter mitochondria, nor does it fuse with the plasma membrane in the context of normal protein - synthesis pathway.

Answer:

binds to a ribosome