NEETBotanyCell Cycle and Cell Division
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In oocytes of some vertebrates, the diplotene stage can last for months or years. Reason (R): The diplotene stage is characterised by the terminalisation of chiasmata and full condensation of chromosomes. In the light of the above statements, choose the correct answer from the options given below:
Options
- A(A) is true but (R) is false.
- BBoth (A) and (R) are true and (R) is the correct explanation of (A).
- CBoth (A) and (R) are true but (R) is not the correct explanation of (A).
- D(A) is false but (R) is true.
Correct answer
A. (A) is true but (R) is false.
Step-by-step solution
Assertion (A) is true because in the oocytes of some vertebrates, the diplotene stage is suspended and can last for months or years. Reason (R) is false because the diplotene stage is characterised by the dissolution of the synaptonemal complex and the recognition of X-shaped chiasmata. The terminalisation of chiasmata and full condensation of chromosomes are the characteristic features of the next stage, diakinesis. Therefore, (A) is true but (R) is false. Answer: (A) is true but (R) is false.