Question

The "R" group amino acids of Glycine, Alanine, and Serine respectively are:

• A. \( CH_2OH; H; CH_2 \)
• B. \( H; CH_2OH; CH_2 \)
• C. \( H; CH_3; CH_2OH \)
• D. \( H; CH_2; CH_2OH \)

Hint:

The R-group defines the chemical properties of amino acids:
- Non-polar (e.g., Alanine: \( CH_3 \))
- Polar (e.g., Serine: \( CH_2OH \))
- Simplest amino acid → Glycine (\( H \)).

Answer 1

The Correct Option is C

Step 1: Understanding Amino Acids and Their "R" Groups
Amino acids consist of a central carbon (C) attached to:
- Amino group (\(-NH_2\))
- Carboxyl group (\(-COOH\)) - Hydrogen (H)
- A unique R-group (side chain) that differentiates each amino acid
For the given amino acids: - Glycine (\(\text{Gly}\)) → The R-group is Hydrogen (H).
- Alanine (\(\text{Ala}\)) → The R-group is Methyl (\(CH_3\)).
- Serine (\(\text{Ser}\)) → The R-group is Hydroxymethyl (\(CH_2OH\)).
Step 2: Identifying the Correct Answer
The correct R-group sequence is: \[ H; CH_3; CH_2OH \] Comparing with the options, we find option (3) is correct.