Histone octamer possesses

Options

A. 8 histones of 4 types
B. 8 types of histones
C. 6 types of histone
D. 5 types of histone

Answer

To solve the question regarding the composition of a histone octamer, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Histone Octamer**:
A histone octamer is a protein complex that plays a crucial role in the structure of DNA within the cell nucleus. It is essential for the formation of nucleosomes, which are the fundamental units of chromatin.

2. **Identify the Components of the Histone Octamer**:
The histone octamer is made up of eight histone proteins. These proteins are categorized into four different types.

3. **List the Types of Histone Proteins**:
The four types of histone proteins that make up the octamer are:
- H2A
- H2B
- H3
- H4

4. **Determine the Number of Each Type of Histone**:
In the histone octamer, there are two copies of each of the four types of histones. Therefore, the total number of histones is:
- 2 (H2A) + 2 (H2B) + 2 (H3) + 2 (H4) = 8 histones in total.

5. **Conclude the Composition of the Histone Octamer**:
Since the histone octamer consists of eight histone proteins made up of four different types, we can summarize that the histone octamer possesses 8 histones of 4 types.

### Final Answer:
The correct answer is that the histone octamer possesses **8 histones of 4 types**.

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