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Defferentiate between leptotene and zygotene |
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Answer» :-Leptotene :-The "Leptotene" stage in meiosis is a stage in which the chromosomes present inside the cell, appear as thin long THREADS. In the "Leptotene" stage, the chromosomes tend to attain a bead like body structure.The bead like structural appearance of the chromosomes is mainly due to the presence of "Chromomeres" in the "Leptotene" stage. Zygotene :-The "Zygotene" stage in meiosis is a stage in which the process of "Synapsis" TAKES place. "Synapsis" is the process through which the pairing of homologous chromosomes occurs. "Synapsis" results in the FORMATION of "BIVALENTS" during the Zygotene stage. Extra Information :-~~~~~~~~~~~~~~~~The process of pairing of chromosomes is highly specific, involving the formation of a special protinaceous structure called the "Synaptonemal complex" (S.C.).The "Synaptonemal complex" (S.C.) is formed during the Zygotene stage only. The "Synaptonemal complex" (S.C.) is associated with the pairing of meiotic chromosomes. The processors of "Genetic recombination" between two homologous chromosomes is facilitated by the "Synaptonemal complex" (S.C.) |
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