$ Nucleosome is present on the chromosomes.
! A true nucleus is called Eukaryon.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To analyze the statements provided in the question, we will break down each statement step by step.

### Step 1: Understand the First Statement
The first statement is "Nucleosome is present on the chromosomes."

- **Explanation**: A nucleosome is a structural unit of a chromosome. It consists of a segment of DNA wrapped around a core of histone proteins. This structure helps in the compaction of DNA, allowing it to fit within the cell nucleus. Therefore, nucleosomes are indeed present on chromosomes.

### Step 2: Evaluate the First Statement
- **Conclusion**: The first statement is **true** because nucleosomes are fundamental components of chromatin, which makes up chromosomes.

### Step 3: Understand the Second Statement
The second statement is "A true nucleus is called Eukaryon."

- **Explanation**: A true nucleus is defined as a membrane-bound nucleus that contains the genetic material of an organism. Eukaryon refers specifically to cells that have a true nucleus, distinguishing them from prokaryotic cells, which do not have a membrane-bound nucleus.

### Step 4: Evaluate the Second Statement
- **Conclusion**: The second statement is also **true** because the term "eukaryon" is indeed used to describe cells with a true, membrane-bound nucleus.

### Step 5: Determine the Correctness of the Explanation
The question asks if both statements are correct and if they provide correct explanations for each other.

- While both statements are true, the first statement does not provide a correct explanation for the second statement. The presence of nucleosomes does not explain what a eukaryon is.

### Final Conclusion
- **Answer**: Both statements are true, but the first statement does not correctly explain the second statement.

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