CELL DIVISION
MEIOSIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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mutation in which the DNA content of the gene is altered
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segregation of sister chromatid
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condensation and segregation of alleles
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crossing-over in which alleles are exchanged
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Detailed explanation-1: -During prophase I, the homologous chromosomes condense and become visible as the x shape we know, pair up to form a tetrad, and exchange genetic material by crossing over. During prometaphase I, microtubules attach at the chromosomes’ kinetochores and the nuclear envelope breaks down.
Detailed explanation-2: -During prophase I, the pairs of homologous chromosomes come together to form a tetrad or bivalent, which contains four chromatids. Recombination can occur between any two chromatids within this tetrad structure.
Detailed explanation-3: -There are 4 sub-phases in meiosis I: • Prophase I: During prophase I, homologous chromosomes line up side by side. They are physically in contact with one another. This process is known as synapsis. Synapsis is when crossing over occurs.
Detailed explanation-4: -When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome.