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Answer» Hey mate ^_^
In single cells of Nicotiana tabacum L. an auxin-only signal induces elongation and DNA endoreduplication.
A subsequent cytokinin +auxin signal induces cell division first as amitosis leading to DNA DEDUPLICATION,then as mitosis coupled to
normal cycling.During the hormone induced cell elongation nuclei endoreduplicate,there DNA content keeping pace with the INCREASING cell volume.
Ultimately cells can increase their nuclear DNA upto about 16 C.When cell division is induced in these elongated cells,the LARGE nuclei divide by amitosis in a seemingly random way as the two daughter nucleido not always fit in binary series of C-values.
During the subsequent amitotic divisions the nuclear DNA content and the cell volume are further reduced.Finally, cells REGAIN mitosis and start cycling on the 2C/4C level, forming microcalli from which normal plantlets can be regenerated
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