REPRODUCTION
EMBRYONIC DEVELOPMENT
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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many body cells
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immune responses
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genetic variation
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natural selection
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Detailed explanation-1: -Meiosis is important because it ensures that all organisms produced via sexual reproduction contain the correct number of chromosomes. Meiosis also produces genetic variation by way of the process of recombination.
Detailed explanation-2: -Genetic variation is increased by meiosis During fertilisation, 1 gamete from each parent combines to form a zygote. Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote.
Detailed explanation-3: -When cells divide during meiosis, homologous chromosomes are randomly distributed to daughter cells, and different chromosomes segregate independently of each other. This called is called independent assortment. It results in gametes that have unique combinations of chromosomes.
Detailed explanation-4: -Genetic variation is also introduced by random fertilization of the gametes produced by meiosis. Any of the genetically unique sperm generated by a male may fertilize the genetically unique egg produced by a female.
Detailed explanation-5: -Meiosis and fertilization create genetic variation by making new combinations of gene variants (alleles). In some cases, these new combinations may make an organism more or less fit (able to survive and reproduce), thus providing the raw material for natural selection.