Class 11 Biology - Chapter Cell cycle and Cell Division NCERT Solutions | Describe the following: (a) synapsis (b)
Describe the following:
(a) synapsis
(b) bivalent
(c) chiasmata
Draw a diagram to illustrate your answer.
(a) Synapsis
The pairing of homologous chromosomes is called synapsis. This occurs during the second stage of prophase I or zygotene.
(b) Bivalent
Bivalent or tetrad is a pair of synapsed homologous chromosomes. They are formed during the zygotene stage of prophase I of meiosis.
(c) Chiasmata
Chiasmata is the site where two non sister chromatids have crossed over. It represents the site of cross-over. It is formed during the diplotene stage of prophase I of meiosis.
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- Q:- Can there be mitosis without DNA replication in S phase?
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