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How does meiosis (including crossing over) lead to increased genetic diversity in a population?

In your response be sure to discuss:

how independent assortment impacts the results of meiosis

how crossing over impacts the results of meiosis

how random fertilization impacts genetic diversity and population

2 Answers

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Meiosis is a type of cell division that produces haploid cells with half the number of chromosomes as the parent cell. The process of meiosis involves two rounds of cell division, resulting in the formation of four genetically unique haploid cells. Meiosis, along with crossing over and independent assortment, leads to increased genetic diversity in a population.

Independent assortment refers to the random distribution of chromosomes during meiosis, where each homologous pair of chromosomes lines up independently of other pairs. This results in an assortment of maternal and paternal chromosomes in each haploid cell. This means that each gamete produced has a unique combination of chromosomes, which can result in an increased number of genetically distinct offspring.

Crossing over is a process that occurs during meiosis I, where homologous chromosomes exchange segments of genetic material. This results in the recombination of alleles between the maternal and paternal chromosomes. This increases genetic diversity by producing gametes that have new combinations of genes that were not present in the parental generation.

Random fertilization is the combination of gametes during fertilization, which results in the formation of a genetically unique zygote. The probability of any two gametes combining during fertilization is very low, which means that the number of possible combinations of genetic material is virtually infinite. This leads to even greater genetic diversity within a population.

Overall, the process of meiosis, along with independent assortment, crossing over, and random fertilization, leads to increased genetic diversity in a population. This increased genetic diversity can help a population better adapt to changing environments, as it allows for a wider range of genetic variation to be selected for by natural selection.

User Joofsh
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Answer:

Meiosis is a process of cell division that occurs in reproductive cells, such as sperm and egg cells, which produces gametes for sexual reproduction. This process involves two rounds of cell division, meiosis I and meiosis II, and in between these two rounds of cell division, genetic material is exchanged between the homologous chromosomes through a process called crossing over. This process results in increased genetic diversity in a population because of two major factors: independent assortment and random fertilization.

Independent assortment occurs during meiosis I, where the chromosomes line up randomly on the metaphase plate and are then distributed equally into the two daughter cells during anaphase. This process increases genetic diversity by creating new combinations of alleles in the gametes.

Crossing over occurs during Prophase I, where non-sister chromatids exchange genetic material. This increases genetic diversity by producing novel combinations of alleles that can be passed on to the next generation.

Random fertilization also has an effect on genetic diversity in a population, because it ensures that each individual in a population is unique, with a different combination of alleles from its parents. This further increases the genetic diversity of a population by providing new combinations of alleles for individuals that can be passed on to the next generation.

User Danny Staple
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