Assertion: DNA replication in a bacterial cell is bidirectional.
Reason: A chromosomes with primary constriction is called "SAT" chromosomes.

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 solve the assertion and reason question, we need to analyze both statements carefully.

### Step 1: Analyze the Assertion
The assertion states that "DNA replication in a bacterial cell is bidirectional."

- In bacterial cells, the DNA is typically in the form of a circular chromosome.
- During DNA replication, a structure called the replisome is formed at the origin of replication.
- The replication process occurs in two directions from the origin, creating two replication forks that move away from each other.
- Therefore, the assertion is **true**.

### Step 2: Analyze the Reason
The reason states that "A chromosome with primary constriction is called 'SAT' chromosomes."

- The term "SAT chromosomes" refers to satellite chromosomes, which are distinct from the main chromosomes.
- Satellite chromosomes are characterized by a secondary constriction, not a primary one.
- Therefore, the reason is **false**.

### Step 3: Determine the Relationship
Now, we need to establish the relationship between the assertion and the reason:

- The assertion is true, while the reason is false.
- The reason does not provide any support or explanation for the assertion.

### Conclusion
Based on the analysis:
- The assertion is correct.
- The reason is incorrect and unrelated to the assertion.

Thus, the correct answer is that the assertion is true, and the reason is false.

### Final Answer
Assertion is true; Reason is false.

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