Is DNA replication possible without cell division?

Asked by Abhisek | 1 year ago |  105

1 Answer

Solution :-

Yes. DNA replication is possible without cell decisions. Endomitosis is the proliferation of chromosomes found in a set in the nucleus without cytokinesis and karyokinesis leads to several copies within each cell. It is of two kinds, which are described below.

i. Polyteny:

• Here chromosomes split and redivide without partition of chromatids so that such chromosomes turned into multistranded with several copies of DNA.

• Such polytene (several stranded) chromosomes persist in the permanent prophase stage and do not endure the cell cycle e.g., polytene salivary glands) the chromosome of Drosophila.

• Here several sets of chromosomes do not change.

ii. Polyploidy (endoduplication)

● Here all chromosomes in a set split and its chromatids are isolated but the nucleus does not split.

● This raises the number of sets of chromosomes in the nucleus ( 4 x, 8 x…..).

● This rise in sets of chromosomes is known as polyploidy. It can be stimulated by colchicine (alkaloid obtained from Colchicum autumnale (family –Liliaceae). These chromosomes are normal and endure a cell cycle.

Answered by Pragya Singh | 1 year ago

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