Based on different functional (R) groups the following amino acids are formed. Select the correct amino acid according to different functional groups.

Options

A. `R rarrH` (glycine)
B. `RrarrCH_3` (alanine)
C. `RrarrCH_2OH` (serine)
D. All the above

Answer

To solve the question regarding the identification of amino acids based on their functional groups, we will analyze each amino acid mentioned in the video transcript step by step.

### Step-by-Step Solution:

1. **Understanding Amino Acids**:
- Amino acids are organic compounds that serve as the building blocks of proteins. Each amino acid contains two essential functional groups:
- A **carboxyl group** (-COOH)
- An **amine group** (-NH2)

2. **Identifying Glycine**:
- Glycine is the simplest amino acid.
- It contains the carboxyl group and the amine group.
- Its side chain consists of just one hydrogen atom (H).
- Therefore, the functional groups for glycine are:
- Carboxyl group: -COOH
- Amine group: -NH2
- Side chain: H
- **Conclusion**: Glycine is correctly represented.

3. **Identifying Alanine**:
- Alanine is another amino acid that contains the carboxyl and amine groups.
- Its side chain consists of a methyl group (CH3).
- Therefore, the functional groups for alanine are:
- Carboxyl group: -COOH
- Amine group: -NH2
- Side chain: -CH3 (methyl group)
- **Conclusion**: Alanine is correctly represented.

4. **Identifying Serine**:
- Serine also contains the carboxyl and amine groups.
- Its side chain consists of a hydroxymethyl group (CH2OH).
- Therefore, the functional groups for serine are:
- Carboxyl group: -COOH
- Amine group: -NH2
- Side chain: -CH2OH (hydroxymethyl group)
- **Conclusion**: Serine is correctly represented.

5. **Final Conclusion**:
- Since all three amino acids (glycine, alanine, and serine) have been correctly identified based on their functional groups, the correct answer to the question is **"all of the above."**