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1. Meiosis creates cells with half the DNA of the parent cell. Specifically, each gamete contains only one set of chromosomes.
2. False. The only cells in your body that can undergo meiosis are the special cells in the ovaries and testes that produce the eggs and sperm.
3. The specialized cells in the ovaries and testes that produce the gametes start off as diploid cells. Once they divide by meiosis, they produce the haploid gametes (egg or sperm). When an egg and sperm fuse in sexual reproduction, it creates a diploid zygote cell.
4. Nothing. The sister chromatids are genetically identical, so if segments switched between the two, there would be no difference.
5. The purpose of sexual reproduction is to create new genetic combinations in the offspring. When each individual creates different variations of egg or sperm, this ensures their offspring will have their own unique genetic makeup.
6. The cell that divides by meiosis to create the gametes is diploid because it contains two sets of chromosomes (referred to as a diploid cell). The resulting gametes (either egg or sperm) contain one set of chromosomes and are called haploid cells.
7. Synapsis occurs when the homologous chromosomes clump together. Also, the pairs of homologous chromosomes (called tetrads) line up in the middle during metaphase I and are split up into separate cells during anaphase I.
8. When the two pairs of homologous chromosomes segregate into separate cells during anaphase I, the resulting daughter cells are haploid (because they contain only one of each homologous chromosome pair).
9. Meiosis creates gametes with different genetic combinations through the process of crossing over (when segments of two homologous chromosomes swap with one another) and independent assortment (the homologous chromosomes line up in a different pattern during metaphase I).
10. d. When a diploid cell begins meiosis, it has two sets of DNA (meaning it has both pairs of homologous chromosomes). Meiosis I results in the homologous chromosomes being separated into two different cells; each resulting cell—which contains only a single set of homologues—is now haploid.