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Cell Cycle PowerPoint Presentation

Cell Cycle

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Cell Cycle

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  1. Cell Cycle The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells.

  2. DNA • Before a cell divides, DNA is copied • DNA is organized into structures called chromosomes • DNA is in the nucleus

  3. Cell Cycle (Prokaryotic) BACTERIA • Bacteria are not complex • Bacteria contain ribosomes and a single circular molecule of DNA • Bacteria have no membrane bound organelles, making cell division simple • Cell division is called binary fission- splitting into two parts • They make a copy of the DNA and split with each cell containing a copy

  4. Binary Fission in Bacteria • Bacteria

  5. Binary Fission • Bacteria

  6. Eukaryotic Cell DivisionCHROMOSOMES • Chromosomes contain lots of DNA and proteins • Number of chromosomes is different in each organism-humans=46, potatoes=48, and fruit flies=8 • Chromosomes can line up in pairs containing similar information (homologous chromosomes)

  7. CHROMOSOMES

  8. Making More Eukaryotic CellsINTERPHASE STAGE 1 • Three stages, Interphase, Mitosis, and Cytokinesis • Stage 1(INTERPHASE)=Cell grows and copies organelles, centriole, and chromosomes • Strands of DNA and proteins are like loosely coiled thread • After chromosomes are duplicated, the copies are now called chromatids • Chromatids are held together by a centromere

  9. INTERPHASE

  10. INTERPHASE

  11. Making More Eukaryotic Cells MITOSIS STAGE 2 • Three stages, Interphase, Mitosis, and Cytokinesis • Stage 2 (Mitosis)Chromosome Separation • 4 Phases OF MITOSIS = Prophase, Metaphase, Anaphase, and Telophase

  12. Mitosis STAGE 2Separation – PHASE1 • Phase 1(Prophase) Mitosis begins • Nuclear membranes break apart • Chromosomes condense into rod like structures • Two pair of centrioles move to opposite sides of the cell • Fibers form between the centrioles and attach to the centromeres

  13. MITOSIS – STAGE 2PHASE 1 PROPHASE

  14. MORE PROPHASE

  15. Mitosis STAGE 2Separation – PHASE 2 • Phase 2 (Metaphase) • Chromosomes line up along the equator of the cell • Remember M for Middle

  16. METAPHASE

  17. MORE METAPHASE

  18. Mitosis – STAGE 2Separation – PHASE 3 • Phase 3 (Anaphase) • Chromatids separate and are pulled to opposite sides of the cell by fibers that are attached to the centrioles • Remember A for Apart

  19. ANAPHASE

  20. ANAPHASE

  21. Mitosis – STAGE 2Separation – PHASE 4 • Phase 4 (Telophase) • Nuclear membrane forms around two sets of chromosomes and they unwind • Fibers disappear • Mitosis is completed • Remember T for Two • The kindergarten teacher said “Do not p on the mat! (PMAT)

  22. TELOPHASE

  23. Stage 3 CYTOKINESIS-Animal Cell • After mitosis, the cytoplasm splits in two, (Cytokinesis) • Result is two identical cells, identical to the original cell they came from • After cytokinesis, cell cycle is complete and will start over again

  24. Stage 3 CYTOKINESIS-Plant Cell • When plant cells divide, a cell plate forms and the cell is split in two • Cell plate becomes the new cellmembrane that will separate the two cells • After split, new cell wall forms

  25. CYTOKINESIS

  26. CELL CYCLE COMPLETE!