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Cellular Division -cells split to make more cells. Why do cells divide?. Repair. Growth. To stay small for metabolism. Asexual. Reproduction. Sexual. 1-Interphase Protein Synthesis Replication 2-Mitosis Cell Division. Main Stages of Cell Life Cycle. Mitosis Steps. 5. 1.
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Why do cells divide? Repair Growth To stay small for metabolism Asexual Reproduction Sexual
1-Interphase Protein Synthesis Replication 2-Mitosis Cell Division Main Stages of Cell Life Cycle
Mitosis Steps 5 1 1. Chromosomes coil up 2. Move to the middle 3. Sister chromatids pulled apart 4. Cells split into 2 identical body cells 5. Chromosomes uncoil to resume protein synthesis 4 2 3
Chromosome # by Species Total # is even 1/2 from mom 1/2 from dad Diploid (2N)= full set of chromosomes
How do you get 1/2 from each parent? Meiosis!= cell division resulting in 4 haploid (1N) gamete cells (egg/sperm)
Sexual Repro by Meiosis increases genetic diversity Haploid egg (1n) + Haploid sperm (1n) = Diploid Zygote (2n)
Mitosis vs Meiosis I • Two divisions • Homologous chromosomes line up • Cross over • Homologous pairs split • Second division sister chromatids split • 4 different (1N) gametes (egg or sperm) II
Homologous Chromosome alignment creates gamete variety (Indep. Assortment) Parent GgYy
Mitosis Meiosis Sister Chromatids line up & split Homologous chromosomes line up & split Diploid (2n) Haploid (1n)