When the following amino acids are separated by running them on Agraose gel at pH 7, which one then will migrate slowest to anode ends ?

Options

A. Aspartic acid
B. Valine
C. Glycine
D. Lysine

Answer

To determine which amino acid will migrate slowest to the anode end when separated by agarose gel at pH 7, we need to analyze the charges of the amino acids involved.

### Step-by-Step Solution:

1. **Understand the Charge of Amino Acids at pH 7**:
At pH 7, amino acids can exist in either a positively charged, negatively charged, or neutral state depending on their side chains (R groups).

2. **Identify Charged Amino Acids**:
Out of the 20 standard amino acids, only a few are charged at physiological pH. The five amino acids that can be charged at pH 7 are:
- **Negatively Charged**: Aspartic acid (Asp) and Glutamic acid (Glu)
- **Positively Charged**: Lysine (Lys), Arginine (Arg), and Histidine (His)

3. **Determine Migration Direction**:
- Negatively charged amino acids (Asp and Glu) will migrate towards the anode (positive end).
- Positively charged amino acids (Lys, Arg, and His) will migrate towards the cathode (negative end).

4. **Identify Which Amino Acid Migrates Slowest**:
Since the question asks for the amino acid that migrates slowest to the anode, we focus on the positively charged amino acids. Among them, all will migrate towards the cathode, but since they are attracted to the opposite end, they will not migrate towards the anode.

5. **Conclusion**:
The amino acid that will migrate slowest towards the anode (positive end) is **Lysine (Lys)**, as it is one of the positively charged amino acids.

### Final Answer:
**Lysine (Lys) will migrate slowest to the anode end.**