Biology CLEP Prep Practice Exam

What does DNA contain?

1. Strings of RNA

2. Proteins

3. Strings of amino acids

4. Strings of nucleotides

The correct answer is: Strings of nucleotides

DNA stands for deoxyribonucleic acid and it contains strings of nucleotides. DNA is a molecule that carries the genetic instructions for the development, functioning, growth, and reproduction of all known living organisms. Option A, strings of RNA, is incorrect because RNA (ribonucleic acid) is a different type of molecule that is involved in the translation of the genetic instructions stored in DNA into proteins. RNA is not the main component of DNA. Option B, proteins, is incorrect because while DNA does code for proteins, it does not physically contain them like it contains nucleotides. Option C, strings of amino acids, is incorrect because amino acids are the building blocks of proteins, not the building blocks of DNA. DNA contains nucleotides, which are different molecules.