Which functional group is present in amino acids but not found in starch?

• A. Amino group (\(-NH_2\))
• B. Glycosidic bond
• C. Methyl group (\(-CH_3\))
• D. Hydroxyl group (\(-OH\))

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by identifying the functional groups listed in the problem: amino group ( $N_2$ ), glycosidic bond, methyl group ( ${\mathrm{CH}}_3$ ), and hydroxyl group ( ${\mathrm{OH}}_{}$ ).
2. Step 2: Recall the structure of amino acids. Amino acids contain two key functional groups: an amino group ( $N_2$ ) and a carboxyl group ( ${\mathrm{COOH}}_{}$ ).
3. Step 3: Consider the structure of starch. Starch is a polysaccharide composed of glucose monomers linked by glycosidic bonds. It primarily contains hydroxyl groups ( ${\mathrm{OH}}_{}$ ) and glycosidic bonds, but it does not contain amino groups ( $N_2$ ).
4. Step 4: Compare the functional groups present in amino acids and starch. The amino group ( $N_2$ ) is unique to amino acids and is not found in starch.
5. Step 5: Conclude that the functional group present in amino acids but not found in starch is the amino group ( $N_2$ ).