Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Primary endosperm is formed earlier than the zygote although the union between the male gamete and egg happens earlier than the union of male gamete with the polar nuclei. Reason (R): Cytoplasm of central cell is more active than the egg. In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is not correct
• D. (A) is not correct but (R) is correct

Hint:

Primary endosperm formation precedes zygote division, and the central cell’s activity plays a role.

Answer 1

The Correct Option is A

Step 1: Concept
Plant Embryology

Step 2: Meaning
Understanding the sequence and timing of events in plant fertilization and early embryo development.

Step 3: Analysis
Statement (A) asserts that primary endosperm formation precedes zygote formation, even though the male gamete fuses with the egg earlier than it does with the polar nuclei. Statement (R) suggests that the central cell’s cytoplasm is more active compared to the egg’s.

Step 4: Conclusion
Primary endosperm formation indeed occurs before the zygotic division, due to double fertilization involving both male gametes. The activity of the central cell's cytoplasm does contribute to this process but does not fully explain it as the underlying mechanism for timing differences in developmental events. Final Answer: (A)