Question: which one of the following lists the chemical components of a nucleotide?
Answer: Each nucleotide consists of a heterocyclic base linked via a five-carbon sugar (deoxyribose or ribose) to a phosphate group (see Figure 4-1). DNA and RNA each contain four different bases (see Figure 4-2). The purines adenine (A) and guanine (G) and the pyrimidine cytosine (C) are present in both DNA and RNA.