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11.4 Meiosis Notes Pages 323-328
Define:
1. Homologous: chromosomes in which one set comes from the male parent and one set
comes from the female parent
2. Diploid: cell that contains two sets of homologous chromosomes
3. Haploid: cell that contains only a single set of chromosomes (genes)
4. Meiosis: process in which the number of chromosomes per cell is cut in half through the
separation of homologous chromosomes in a diploid cell
5. Tetrad: structure containing four chromatids that forms during meiosis
6. Crossing-Over: process in which homologous chromosomes exchange portions of their
chromatids during meiosis
7. Zygote: fertilized egg
8. Gamete: sex cell
Include all of the Key Answers from page 323-328, stopping before Gene Linkage and Gene
Maps
1. The diploid cells of most adult organisms contain two complete sets of inherited
chromosomes (two complete sets of genes)
2. In prophase I of meiosis, each replicated chromosome pairs with its corresponding
homologous chromosome.
3. During metaphase I of meiosis, paired homologous chromosomes line up across the
center of the cell.
4. During anaphase I, spindle fibers pull each homologous chromosome pair toward
opposite ends of the cell
5. The next phase is telophase I, in which a nuclear membrane forms around each cluster
of chromosomes. Cytokinesis follows telophase I, forming two new cells.
6. As the cells enter prophase II, their chromosomes—each consisting of two chromatids—
become visible.
7. The final four phases of meiosis II are similar to those in meiosis I. However, the result is
four haploid daughter cells.
8. In mitosis, when the two sets of genetic material separate, each daughter receives one
complete set of chromosomes. In meiosis, homologous chromosomes line up and then
move to separate daughter cells.
9. Mitosis does not normally change the chromosome number of the original cell. This is
not the case for meiosis, which reduces the chromosome number by half.
10. Mitosis results in the production of two genetically identical diploid cells, whereas
meiosis produces four genetically different haploid cells.
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