Justify the effects of a change in the cell cycle mitosis and/or meiosis will have on chromosome structure, gamete viability, genetic diversity, and evolution.
A change in the cell during mitosis or meiosis can cause cell division to go awry. Chromosomes may duplicate oddly, crossover in incorrect ways, etc. The end result may create two defective daughter cells. As a result, the gamete may not be as viable. For example, down syndrome occurs when there is an extra copy of chromosome 21 created during meiosis. But, such DNA mutations can drive evolution, and explain diversity.
Evolution, by definition, is genetic mutation. These mutations occur to help a species adapt to a specific environmental factor.
As for diversity, Meiosis I & Meiosis II [See Stages of Meiosis] have events such as crossing over, reduction to haploid cells, and random chromatid assignment that can lead to creating a unique set of DNA that eventually grows into a fully formed organism. This is why there is such diversity within species, there are plenty of different combinations of DNA, and typically no DNA is the exact same.
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