Identify the given phase and give reason to support your answer
The nuclear membrane and nucleolus both disappear during prophase of mitosis and meiosis. The nucleolus is a region of the interphase nucleus containing many of the genes that code for ribosomal RNAs (r RNAs). The genes are on a number of different chromosomes, which have to folded in such a way that these genes end up in the same region of the nucleus. During prophase the chromosomes separate from one another, and so the nucleolus disappears.
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