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Mitosis [compatibility mode]

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  • 1. CELL CYCLE

2. The Cell Cycle Cells must divide to maintain maximumefficiency. Mitosis is the process in which somatic(body) cells divide to form a new cell. Mitosis consists of four phases. Interphase is the period in between eachmitotic cell division. 3. Reproduction Asexual Reproduction: A single cell or group ofcells each duplicates its genetic material and thensplits into two new genetically identical cells. The offspring are genetically identical Sexual Reproduction: Genetic material from eachof two parents combines, producing offspring thatdiffer genetically from either parent. Involves the union of sex cells (egg and sperm) 4. Parent cellDNA replicates Cell division = One cell makes two cellsTwo daughter cellsare genetically identical to eachother and to parent cell = clones 5. The same DNA can appear in two formsChromatin = uncondensed DNA Chromosome = condensed DNA 6. 1 Chromosome1 chromatid per chromosome1 DNA double helixDNA replication1 Chromosome2 chromatids per chromosome2 DNA double helices 7. Cell division in eukaryotic cells:Cytokinesis = division of the cytoplasm 8. Interphase Interphase is made of 3 stages. The Gap 1 and 2 or G1 and G2 phase is whencells grow and make RNA, proteins, and othermacromolecules. The S or Synthesis phase is when the cell ismaking DNA. 9. DNA Replication During the S phase of the cell cycle, DNAreplicates. A short section of the DNA uncoils. New nucleotides bond to the open sections ofthe DNA. The new and old sections of DNAseparate and now there are 2 DNA strands. 10. Interphase ATP is synthesized. Damaged parts are repaired. Wastes are excreted. Proteins are made. Organelles are formed. Chromosomes are copied. Specialized tasks are performed . 11. Interphasenucleus DNA = Chromatin 12. InterphaseChromatinin nucleus 13. Mitosis Mitosis consists of four phases Prophase Metaphase Anaphase Telophase 14. Prophase Longest phase. Chromatin coils. Nucleus disappears. Centrioles migrate. Spindle forms. 15. Prophase Nuclear membrane disappears Nucleolus disappears Chromatin condenses into chromosomes Spindle fibers appear 16. ChromatinChromosomes 17. Metaphase Chromatids attach to spindle fibers. Chromatids migrate to equator of spindle. 18. Metaphase Chromosomes line up in center of cell 19. Centromere = holds chromatids together Chromatids (DNA double helix)Two chromatids per chromosome 20. Anaphase Centromere splits. Chromatids are separated. Chromatids are now called chromosomes. 21. Anaphase =Sister chromatids separatefrom each other 22. Telophase Cytoplasm divides. Nucleus reappears. Chromosomes uncoil. 23. Telophase Cytokinesis makes 2 new cells Chromosomes decondense into chromatinNucleolus reappearsNuclear membrane reappears 24. Early TelophaseLate Telophase 25. Cytokinesis In the process calledcytokinesis, the cytoplasmdivides and two identicaldaughter cells are formed. 26. Plant cellAnimal cell Cytokinesiswall growsmembranes between twopinches new cellstogetherbetween two new cells 27. InterphaseProphaseProphaseTelophaseMetaphase AnaphaseTelophase Telophase PlantCytokinesis = division of cytoplasm 28. InterphaseProphaseMetaphase Animal cytokinesis =pinching of plasmaAnaphasemembraneLate Telophase Early telophase 29. Plant orAnimal cell mitosis?Plant