Question

Why is rna necessary to act as a messenger? why cant the code be taken directly from the dna

Answer 1

Messenger RNA (mRNA) is necessary for transporting instructions from DNA in the nucleus to the ribosomes in the cytoplasm for protein synthesis. It serves as a temporary copy of the genetic information, activated only when needed.

Step-by-step explanation:

RNA is essential as a messenger because it carries the genetic code from DNA to the ribosomes, where proteins are synthesized. DNA is confined to the nucleus while protein synthesis occurs in the cytoplasm, necessitating a messenger RNA (mRNA) to bridge the gap. Moreover, mRNA is crucial because its structure allows it to be a temporary, disposable copy of the genetic information, designed to be read and utilized by the cell's machinery only when a certain protein needs to be made. An example is when the DNA sequence 5'-AATTGCGC-3' is transcribed into the RNA sequence 3'-UUAACGCG-5', demonstrating mRNA's role in carrying accurate instructions for protein assembly.

Answer 2

Because there's one copy of the gene in DNA (2 for diploid species including humans). It would take a LONG time to make an appreciable amount of protein from two copies of the gene. But the cell can make many copies of mRNA to quickly make larger amounts of the desired protein.