Upon examination, a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA. All of the DNA is found within a single nucleus. Which stage of the cell cycle is this cell in?

The Gap 2(G2) stage of Interphase

Explanation:

In a eukaryotic cell, the cell cycle refers to both -cell growth and cell division - leading to the production of identical daughter cells. The cell cycle is basically divided into interphase (I) and mitosis (M).

The interphase, during which the cell grows and replicates its DNA takes place by the following stages – Gap 1 (G1), Synthesis (S), Gap 2(G2).

The cells grow and increase in size during the G1 period.

The G2 phase or the second gap phase the cell utilizes energy and produces necessary proteins for undergoing chromosome manipulation and other organelles and prepares the cell for mitotic cell division.

DNA replication mainly takes place in the Synthesis or the S stage of interphase with each of the chromosomes (46) is replicated.  

Due to this DNA replication in the S stage, its content is doubled (4-N DNA content) when it enters the G2 stage and all the DNA is found within a single nucleus.

this protocol provides a detailed procedure for chromatin immunoprecipitation (chip) to study the dna-protein interactions.

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