CELL DIVISION
THE CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The cell had mutated
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The cell was in the G2 phase
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The cell was in the G1 phase
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The cell was in the G0 phase
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Detailed explanation-1: -The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA. In this way, the genetic material of a cell is doubled before it enters mitosis or meiosis, allowing there to be enough DNA to be split into daughter cells.
Detailed explanation-2: -Thus, if cell has twice as much DNA as in a normal functional cell, it means that the cell is preparing to divide.
Detailed explanation-3: -After DNA replication is completed in the S phase, the cell enters the G2 phase and has twice the amount of the DNA (4N) of the starting cell. This is followed by mitosis (M) and cell division, which leads to the formation of two diploid daughter cells.
Detailed explanation-4: -During S phase, which follows G1 phase, all of the chromosomes are replicated. Following replication, each chromosome now consists of two sister chromatids (see figure below). Thus, the amount of DNA in the cell has effectively doubled, even though the ploidy, or chromosome count, of the cell remains at 2n.