Question

which functional groups are present in nucleic acids? see figures below. if you are having trouble seeing the figure then click this link to see the figure in a new window: nucleic acid functional groups need a hint? check out this version of the figure that has all of the functional groups circled: nucleic acid functional groups circled ☐ amino ☐ hydroxyl ☐ sulfhydryl ☐ methyl ☐ carboxyl

Explanation:

1. Amino Group ($-\text{NH}_2$): The nitrogen - containing bases in nucleic acids (like adenine, guanine) have amino groups ($-\text{NH}_2$) attached to the heterocyclic rings. From the given structure, we can see the $\text{H}_2\text{N}-$ groups, which are amino groups.
2. Hydroxyl Group ($-\text{OH}$): The sugar (ribose or deoxyribose) part of the nucleic acid monomer (nucleotide) has hydroxyl groups. In the provided structure, we can identify $-\text{OH}$ groups (e.g., the $-\text{OH}$ on the sugar ring and the $-\text{OH}$ in the phosphate - related group $\text{HO}-$).
3. Sulfhydryl Group ($-\text{SH}$): There is no sulfur - containing group ($-\text{SH}$) visible in the structure of nucleic acids (nucleotides) as shown. Nucleic acids do not typically have sulfhydryl groups.
4. Methyl Group ($-\text{CH}_3$): The given structure does not show any methyl groups ($-\text{CH}_3$). Methylation of nucleic acids (like DNA) occurs at specific sites but is not a part of the basic nucleotide structure shown here.
5. Carboxyl Group ($-\text{COOH}$): The structure does not have a carboxyl group ($-\text{COOH}$) as nucleic acids (nucleotides) do not have this functional group in their basic structure.

Answer:

• Amino (the structure has $\text{H}_2\text{N}-$ groups)
• Hydroxyl (the structure has $-\text{OH}$ groups, e.g., on the sugar and in $\text{HO}-$)