Assertion: The DNA contents are usually constant in a given species.
Reason: DNA replication is of continuous type.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. If Assertion is true but the Reason is false.
D. If both Assertion and Reasom are false.

Answer

To analyze the assertion and reason provided in the question, let's break down the statements step by step.

### Step 1: Analyze the Assertion
The assertion states: "The DNA contents are usually constant in a given species."

- **Explanation**: This statement is true. In a particular species, the DNA content is generally consistent across individuals. For example, humans have a specific amount of DNA (approximately 6.6 billion base pairs) that is consistent among all human cells. This consistency is due to the fact that all individuals of a species share the same number of chromosomes and the same amount of genetic material.

### Step 2: Analyze the Reason
The reason states: "DNA replication is of continuous type."

- **Explanation**: This statement is false. DNA replication is not entirely continuous. It involves two types of strands during replication: the leading strand and the lagging strand. The leading strand is synthesized continuously in the 5' to 3' direction. However, the lagging strand is synthesized in short segments called Okazaki fragments, which means it is synthesized discontinuously. Therefore, the process of DNA replication is better described as semi-discontinuous.

### Step 3: Conclusion
Based on the analysis:
- The assertion is true.
- The reason is false.

Thus, the correct answer to the question is that the assertion is true, but the reason is false.

### Final Answer:
The correct conclusion is: Assertion is true but reason is false.

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