LABORATORY REVIEW
MITOSIS AND MEIOSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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transcription
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crossing over
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nondisjunction
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genetic shuffling
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Detailed explanation-1: -Definition. Crossing over, as related to genetics and genomics, refers to the exchange of DNA between paired homologous chromosomes (one from each parent) that occurs during the development of egg and sperm cells (meiosis).
Detailed explanation-2: -During prophase I, homologous chromosomes pair with each other and exchange genetic material in a process called chromosomal crossover. The exchange occurs in segments over a small region of homology (similarity in sequence, ie., the same alleles).
Detailed explanation-3: -So, the correct answer is ‘Crossing over produces new combinations of genes on alleles, increasing genetic variation.
Detailed explanation-4: -Specifically, meiosis creates new combinations of genetic material in each of the four daughter cells. These new combinations result from the exchange of DNA between paired chromosomes. Such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation.
Detailed explanation-5: -Exchange of segments between non sister chromatids of homologous chromosomes is called crossing over.