Question: 108 The process of appearance of recombination nodules occurs at which sub stage of prophase I in meiosis?
(1) Diplotene
(2) Diakinesis
(3) Zygotene
(4) Pachytene
Answer: Option (4)
Explanation:
Prophase I of meiosis is divided into leptotene, zygotene, pachytene, diplotene, and diakinesis.
During pachytene stage, homologous chromosomes are completely synapsed and form bivalents.
At this stage, recombination nodules appear on the synaptonemal complex.
These recombination nodules are the sites where crossing over occurs between non-sister chromatids of homologous chromosomes.
Thus, the appearance of recombination nodules is a characteristic feature of the pachytene stage of prophase I.