CELL DIVISION
CELL DIVISION AND CANCEROUS CELLS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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So that it can fix any mistakes the cell made during division
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So that the cell can get bigger
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So that each new cell will have a full set of chromosomes after mitosis
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So that each cell has a back-up copy of its DNA
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Detailed explanation-1: -Cells must replicate their DNA before they can divide. This ensures that each daughter cell gets a copy of the genome, and therefore, successful inheritance of genetic traits.
Detailed explanation-2: -Many of the genes on each chromosome give the instructions for making a large number of proteins that are needed for normal cell structure and function. Therefore, each cell needs to have a complete set of chromosomes with all of these genes.
Detailed explanation-3: -Following DNA replication, the DNA content doubles again to 4c, but each pair of sister chromatids is still counted as a single chromosome (a replicated chromosome), so the number of chromosomes remains unchanged at 2n.
Detailed explanation-4: -Before mitosis occurs, a cell’s DNA is replicated. This is necessary so that each daughter cell will have a complete copy of the genetic material from the parent cell.
Detailed explanation-5: -Mitosis occurs after DNA replication because DNA replication doubles the number of chromosomes, and mitosis separates the two new sets of chromosomes into separate nuclei, and then the cell divides.