Assertion : Somaclonal variations may be present in plants produce from callus.
Resons : Somaclonal variations are caused due to recombination during meiosis.

Options

A. both a and r are true and r is the correct explantion of a
B. both a and r true but r is not the correct explanation of a
C. a is true but r is false
D. a is false but r is true

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Somaclonal variations may be present in plants produced from callus." Somaclonal variation refers to the genetic variation observed in plants that arise from somatic cells, particularly those cultured in vitro. Callus is a mass of undifferentiated cells that can be induced from plant tissues and is a common starting point in plant tissue culture.

2. **Evaluating the Reason**: The reason provided is "Somaclonal variations are caused due to recombination during meiosis." Meiosis is a type of cell division that reduces the chromosome number by half and is involved in sexual reproduction, leading to genetic recombination. However, somaclonal variations arise from somatic cells, which do not undergo meiosis.

3. **Analyzing the Relationship**: The assertion is true because somaclonal variations can indeed occur in plants derived from callus tissue. However, the reason is false because somaclonal variations are not caused by recombination during meiosis, as these variations arise from mutations in the somatic cells during tissue culture, not from meiotic processes.

4. **Conclusion**: Therefore, the assertion is true, and the reason is false. The correct answer is that the assertion is true and the reason is false.

**Final Answer**: Assertion is true and Reason is false.

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