Answer:
C
Explanation:
The helix has to unwind before separating. Once it's separated, then new bases can be added. Once the bases are added, the separate strands wind into helices.
Skin cells are made of proteins, water, and fat. But brain cells are only made up of amino acids, which ca make protein.<span />
Answer:
number of nitrogen bases
Explanation:
<em>The correct answer would be the number of nitrogen bases.</em>
<u>A defective protein is usually caused by mutation, which is defined a change in the DNA sequence of an organism.</u>
Mutation can occur in a variety of ways including:
<em>1. Deletion of nucleotide base sequence in the DNA</em>
<em>2. Addition (insertion) of nucleotide base sequence in the DNA</em>
<em>3. Duplication of nucleotide sequence in the DNA</em>
<u>A change in number of phosphate molecules, sequence of subunits DNA and sequence of sugar molecules if possible in nature, do not lead to mutation if the change does not affect the sequence of DNA.</u>
Hence, the correct option is number of nitrogen bases.
