Number of cyclic tripeptides formed with 2 amino acids A and B is:

Options

A. `2`
B. `4`
C. `3`
D. `5`

Answer

To determine the number of cyclic tripeptides that can be formed using two amino acids, A and B, we can follow these steps:

### Step 1: Understand the Problem
We need to form cyclic tripeptides using two types of amino acids, A and B. A tripeptide consists of three amino acids.

### Step 2: Determine the Number of Positions
Since we are forming a cyclic tripeptide, we will have three positions to fill with either amino acid A or B.

### Step 3: Use the Formula
The number of different combinations of amino acids can be calculated using the formula \(2^n\), where \(n\) is the number of positions (or amino acids) in the tripeptide. In this case, \(n = 3\).

### Step 4: Calculate the Combinations
Using the formula:
\[ 2^3 = 8 \]
This means there are 8 different combinations of the amino acids A and B that can form cyclic tripeptides.

### Step 5: List the Combinations
The possible combinations of the cyclic tripeptides are:
1. A-A-A
2. A-A-B
3. A-B-A
4. A-B-B
5. B-A-A
6. B-A-B
7. B-B-A
8. B-B-B

### Conclusion
Thus, the total number of cyclic tripeptides that can be formed using the two amino acids A and B is **8**.

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