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The evolutionary significance of sexual reproduction

Please explain the importance of sexual reproduction, not only in terms of continuation of the species, but in evolutionary terms as well.

Please compare the different types of life cycles exemplified by Chlamydomonas, corn (maize), and humans. Be sure to indicate which stage(s) is (are) dominant in each life cycle. As you can see in these three life cycles, those of higher organisms tend to emphasize the diploid stages more than the haploid stages. Explain why there has been a trend toward diploidy among higher organisms; what are the advantages of being diploid?

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Sexual reproduction is important for 2 reasons. The first is the obvious reason for continuance of the species. However, there is another reason which is evolutionarily important, which is as follows: there is more genetic variation in organisms that reproduce sexually. This is evolutionarily important because it is genetic variation ( mutation) which drives the process of natural selection. This is turn leads to evolution.

Consider the following scenario. I am a marine iguana in a population of many iguanas, that live in the desert areas of the Galapagos. I have a gene or several genes, which allow me to drink sea water and then expel the excess salt without offsetting the tonicity of my cells. I would be able to survive and reproduce during a drought when no fresh water or very little is necessary. When I reproduce that trait will get passed on to some of my offspring, they will then be able to survive and reproduce. This particular trait has been selected for in this particular environment. Eventually, a new species of iguana will emerge. Where did this ...

Solution Summary

this solution discusses the importance of sexual reproduction for evolution and compares the life cycles of human,corn and chlamydomonas.

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