The total number of homo-and hetero-dipeptide that can be obtained formed from glycine and alanine is

Options

A. 4
B. 3
C. 2
D. 1

Explanation

To determine the total number of homo- and hetero-dipeptides that can be formed from glycine and alanine, we can follow these steps:

### Step 1: Understand the Definitions
- **Homo-dipeptides**: Dipeptides formed from two identical amino acids.
- **Hetero-dipeptides**: Dipeptides formed from two different amino acids.

### Step 2: Identify the Amino Acids
In this case, we have two amino acids:
1. Glycine (Gly)
2. Alanine (Ala)

### Step 3: Calculate Homo-dipeptides
- The homo-dipeptides that can be formed are:
1. Glycine + Glycine (Gly-Gly)
2. Alanine + Alanine (Ala-Ala)

Thus, there are **2 homo-dipeptides**.

### Step 4: Calculate Hetero-dipeptides
- The hetero-dipeptides that can be formed are:
1. Glycine + Alanine (Gly-Ala)
2. Alanine + Glycine (Ala-Gly)

Thus, there are **2 hetero-dipeptides**.

### Step 5: Total Dipeptides
- Adding both homo- and hetero-dipeptides together:
- Total = Homo-dipeptides + Hetero-dipeptides
- Total = 2 + 2 = 4

### Conclusion
The total number of homo- and hetero-dipeptides that can be formed from glycine and alanine is **4**.

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