That should be the cell membrane. The cell membrane acts as a filter in and out.
DNA<span> and </span>RNA,<span> are </span>made<span> from monomers known as nucleotides.</span>
Really bro just google it
A missense mutation is a mistake in the DNA which results in the wrong amino acid being incorporated into a protein because of change, that single DNA sequence change, results in a different amino acid codon which the ribosome recognizes.