Understanding the DNA Molecule: Adenine and Thymine Ratio

The Role of Adenine and Thymine in DNA

DNA, or deoxyribonucleic acid, is a complex molecule that contains the genetic instructions for the development, functioning, growth, and reproduction of all living organisms. It consists of four nucleotides: adenine (A), guanine (G), cytosine (C), and thymine (T). These nucleotides form pairs within the DNA double helix structure.

Adenine and thymine are complementary base pairs in DNA, meaning they always pair together. The ratio of adenine to thymine in a DNA molecule is 1:1, indicating that for every adenine molecule, there is a thymine molecule present.

The Question: Calculating Thymine Molecules

If in a strand of DNA there are 1 million adenine molecules, how many thymine molecules are expected to be present in the same strand?

What is the expected number of thymine molecules in the DNA strand?

The correct answer is A) 1 Million.

Since the ratio of adenine to thymine is 1:1 in a DNA molecule, for every adenine molecule, there is a corresponding thymine molecule. Therefore, with 1 million adenine molecules present, 1 million thymine molecules are expected to be in the same DNA strand.