Answer: (4) Uracil
Nucleotide monomers make up DNA. A nitrogenous base is bound to the deoxyribose sugar with the phosphate moiety in each nucleotide.
- Adenine (A), guanine (G), cytosine (C), and thymine (T) are the four nitrogenous bases present in DNA.
- Purine bases are adenine and guanine, while pyrimidine bases are cytosine and uracil.
- Hydrogen bonds connect the nitrogenous bases of the double helix in DNA.
- Adenine and thymine form a pair, while guanine and cytosine form a pair.