Question

a simplified model of protein synthesis is shown below. how might this model be revised to show a more accurate depiction of protein synthesis? a between processes 1 and 2, the mrna must leave the nucleus. b prior to process 1, dna should copy itself to allow the cell to divide. c after process 2, the completed protein should travel back to the nucleus. d during process 2, the ribosome should remove any mutated nucleotides from the mrna

Explanation:

In protein synthesis, transcription (Process 1) occurs in the nucleus where DNA is transcribed into mRNA. Then, the mRNA must leave the nucleus to reach the ribosomes in the cytoplasm for translation (Process 2) to occur. Option B is about DNA replication for cell - division which is not part of this protein - synthesis model. Option C is incorrect as proteins do not travel back to the nucleus after synthesis. Option D is wrong as ribosomes do not remove mutated nucleotides from mRNA.

Answer:

A. Between processes 1 and 2, the mRNA must leave the nucleus.