Discuss the stages events and significance of somatic and reproductive cell

Discuss the stages events and significance of somatic

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7.Discuss the stages, events and significance of somatic and reproductive cell division.
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II. Reproductive cell division – mechanism that produces gametes. Consists of a special two-step division called meiosis where the number of chromosomes in the nucleus is reduced by half C. cell cycle in somatic cells – an orderly sequence of events in which a cell duplicates its contents and divides into 2 I. homologous chromosomes – human cells contain 23 pairs of chromosomes, one member from each pair is inherited from each parent and the 2 chromosomes that make up each pair are called II. sex chromosomes, X and Y – XX for females and XY for males. Y is much smaller than X. III. diploid cell (2n) – because somatic cells contain 2 sets of chromosomes they are called diploid cells a. Interphase – cell replicates DNA and produces additional organelles and cytosolic components in anticipation of cell division. Is a state of high metabolic activity: it is during the time that the cell does most of its growing. Contains 3 phases: G1, S, & G2. S stands for synthesis of DNA and G for gaps as there is no activity related to DNA replication b. G1 phase – interval between mitotic phase and the S phase. Cell is metabolically active replicating organelles and cytosolic components c. G0 state – cells that remain in G! for a very long time, perhaps destined never to divide again d. S phase – ~8 hours long. DNA replication occurs causing the 2 identical cells formed to have the same genetic material e. G2 phase – interval between S phase and mitotic phase. 4-6 hours long. Cell growth continues, enzymes and other proteins are synthesized in preparation for cell division and replication of centrosomes is completed. f. mitotic (M) phase – results in the formation of 2 identical cells, which consists of a nuclear division (mitosis) and cytoplasmic division (cytokinesis) to form 2 identical cells
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