Mitosis maintains the chromosome number, ensuring each daughter cell receives an identical set of chromosomes as the parent cell.
Mitosis is a type of cell division that results in two daughter cells, each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth. The crucial point is that the chromosome number does not change during mitosis. Here's a breakdown:
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Starting Point: A cell preparing for mitosis has already duplicated its chromosomes during the S phase of interphase. Each chromosome consists of two identical sister chromatids attached at the centromere. So, although the amount of DNA is doubled, the number of chromosomes remains the same.
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The Process: During mitosis, the sister chromatids separate and are pulled to opposite poles of the cell.
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The Outcome: When the cell divides into two daughter cells (cytokinesis), each daughter cell receives one copy of each chromosome. Since each daughter cell receives a full and identical set of chromosomes, the chromosome number is identical to that of the original parent cell. For example, in human cells undergoing mitosis, the starting cell has 46 chromosomes (in duplicated form), and each daughter cell also has 46 chromosomes.
In Summary: Mitosis doesn't change the number of chromosomes; it simply ensures that each new cell receives an exact copy of the existing chromosomes. This is essential for growth, repair, and asexual reproduction, where genetic consistency is critical.
