BIOS-251: Exam 2 Review with Verified Solutions

BIOS-251: Exam 2 Review with Verified Solutions Cell division in which the nucleus divides into nuclei containing the same number of chromosomes Mitosis The resting phase of mitosis. Cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases Interphase Cells that have left the cycle and cease dividing for a long time (or permanently) G Zero (G0) Phase The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins. G1 Phase The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated. S Phase The second gap, or growth phase, of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs. Growth and preparation for mitosis G2 Phase First and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus Prophase Second phase of mitosis, during which the chromosomes line up across the center of the cell Metaphase The third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles Anaphase The final phase of cell division, between anaphase and interphase, in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed. Telophase Division of the cytoplasm during cell division Cytokinesis Cell division that produces reproductive cells (gametes) in sexually reproducing organisms Meiosis Compare and Contrast Mitosis and Meiosis Mitosis produces two diploid (2n) somatic cells that are genetically identical to each other and the original parent cell, whereas meiosis produces four haploid (n) gametes that are genetically unique from each other and the original parent (germ) cell. Number of Chromosomes in Humans... 46 Haploid Number of Chromosomes In Humans 23 Control center of the cell; a part of the cell containing DNA and RNA and responsible for growth and reproduction Nucleus