cell cycle and mitosis organization of the process of cell division!
TRANSCRIPT
Cell Cycle and Mitosis
Organization of the process of cell division!
“Omnis cellula e cellula”
Rudolf Virchow
1855
Types of Cell Division
• Binary Fission– Prokaryotic Cell
Division
• Mitosis– Eukaryotic Cell
Division
• Meiosis– Production of sex cells
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Do all cells divide?
• Cells that divide– Stem Cells
– Glial cells in the brain
– Skin cells
– Cancer cells
• Cells that don’t really divide (senescence)– Red Blood Cells
– Neurons
– Heart Cells
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Why might a cell need to divide?• Embryonic Development• Repair Tissues• Cells have a max surface area to volume ratio• Asexual reproduction• Cancer
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Cell Cycle in Eukaryotes
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What is the meaning of mitosis?
• Interphase
• Mitosis
• Cytokinesis
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How is the genetic material organized
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How does the cell change during the cell cycle?
• Are the stages discreet or continuous?
• What is important about metaphase?
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How are changes in genetic material detected?
• Changes in nuclear material first detected by dark stain of the nuclear material = “Chromo”
• Advances in light microscopy show role of centrosomes, spindle fibers, kinetochores
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Phases of mitosis
• See pg 232
• Note activity of chromosomes, envelope, spindle during each stage
• Chromosome “walking”
• Review: Biovisions video
What tells a cell to divide?• External Controls
– Growth Factors
• Internal Controls– Cyclins– CDK
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What proteins control cell growth internally?
• CDK: always present in cells• Cyclin: level varies throughout the cell cycle• MPF: “mitosis promoting factor” --occurs when
cyclin binds to CDK.
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How does cyclin’s
structure allow for its function of promoting
mitosis?
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Cancer
• Cancer is when the cell cycle goes wrong.
• What might happen to cause a cell cycle to wreak havoc?
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