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Why do diploid cells need to reduce their chromosome number by half before fertilization occurs?

User Grishka
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Final answer:

Diploid cells reduce their chromosome number by half through meiosis to prevent doubling of chromosome count in each generation and ensure the created zygote has the correct ploidy level.

Step-by-step explanation:

Diploid cells need to reduce their chromosome number by half before fertilization in order to maintain a constant chromosome count in organisms across generations. Sexual reproduction involves the fusion of two haploid gametes, one from each parent; these gametes each contain one set of chromosomes. At fertilization, these two sets combine to form a diploid zygote with two sets of chromosomes. Without this reduction through meiosis, the chromosome number would double with each generation, leading to a continual increase in chromosome number which is not viable for the survival of species.

Meiosis is a special type of cell division in which a single diploid cell divides to produce four haploid cells, each with half the number of chromosomes. This reduction is crucial because it allows for genetic diversity while preserving the ploidy level of the species. Consequently, it ensures that the resulting zygote has the correct number of chromosomes: not doubled, as would happen if two diploid cells fused together.

User Som Poddar
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Answer:

Meiosis refers to a reductional division, which is essential in the sexually reproducing species to sustain the specific number of chromosomes. The sex cells or the gametes need to have half of the number of chromosomes in comparison to what the parent cell exhibit.

At the time of fertilization, if these gametes possess a similar number of chromosomes like the parent has than each generation would contain double the number of chromosomes as constituted by the parents. In order to prevent this, meiosis takes place in the gonads, that is, testes and ovaries.

User Nuncjo
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