CELL DIVISION
MEIOSIS AND GENETIC VARIATION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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sister chromatids
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homologous chromosomes
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Detailed explanation-1: -In metaphase I, the tetrads line themselves up at the metaphase plate and homologous pairs orient themselves randomly. In anaphase I, centromeres break down and homologous chromosomes separate. In telophase I, chromosomes move to opposite poles; during cytokinesis the cell separates into two haploid cells.
Detailed explanation-2: -Homologue pairs separate during a first round of cell division, called meiosis I. Sister chromatids separate during a second round, called meiosis II.
Detailed explanation-3: -1st Division (Reduction Division) During anaphase I, the homologous chromosome pairs separate and are pulled to opposite poles of the cell by spindle fibers attached to the centrioles.
Detailed explanation-4: -In meiosis I, chromosomes in a diploid cell resegregate, producing four haploid daughter cells. It is this step in meiosis that generates genetic diversity. DNA replication precedes the start of meiosis I. During prophase I, homologous chromosomes pair and form synapses, a step unique to meiosis.