Copy of Mitosis powerpoint presentation.pptx

Copy of Mitosis powerpoint presentation.pptx

• 1.
  Mitosis It’s cell cycletime! 10th Grade
• 2.
  Whoa! Why do wecare about mitosis?
• 3.
  Cell Division ❖ Beforea cell grows too large, it divides into two new daughter cells through a process called “cellular division.” ❖ Each daughter cell must receive a complete set of DNA. ❖ Before cell division, a cell must copy its DNA. (This is DNA replication!)
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  Asexual Reproduction ❖ Inmulticellular organisms, cell reproduction is how you grow! ➢ This also allows an organism to repair itself. ❖ In single-celled organisms, cellular division is a kind of asexual reproduction. ❖ This kind of reproduction only needs 1 parent- and leads to genetically identical offspring.
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  03 Bacteria reproduce bybinary fission. Starfish can reproduce by fragmentation. 02 Fragmentation 01 Asexual Reproduction Examples Hydras reproduce by budding. Budding Binary Fission
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  Asexual vs. SexualReproduction
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  Chromosomes Genetic information iscarried by chromosomes Remember that chromosomes are condensed/tightly packed coils of DNA Each daughter cell gets its own copy of the genetic information Cells of every organism have a specific number of chromosomes.
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  Prokaryotic Cell Cycle Theprokaryotic cell cycle is a pattern of growth, DNA replication, and then cell division. Most begin to copy their DNA once they reach a certain size. When DNA replication is complete, the cells divide through binary fission.
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  Eukaryotic Cell Cycle TheEukaryotic Cell cycle has four phases: G1, S, G2, and M. Interphase is the time of growth where the cell performs its normal functions. It includes G1, S, and G2 phases. The M phase is the time for cell division.
• 10.
  Cells increase in sizeand make new proteins and organelles Eukaryotic Cell Cycle M phase Mitosis is the division of the cell nucleus Cytokinesis is the division of the cytoplasm or body of the cell. G2 The organelles required for division are made. Cell is preparing for mitosis G1 S - Phase DNA replication takes place and chromosomes are duplicated
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  Important Structures~ These are allimportant for mitosis ● Chromatid - each strand of a duplicated chromosome ● Centromere - the area where chromosomes are joined ● Centrioles - tiny structures in the cytoplasm that help organize the spindle fibers ● Spindle - a fan like structure that helps to pull apart the chromatids.
• 12.
  During the firstphase of mitosis, the duplicated chromosomes condense, and become visible in the nucleus. The centrioles move to opposite sides of the nucleus and help organize the spindle. The spindle forms and DNA strands attach at the centromere. The nucleus begins to break down Prophase
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  During the secondphase, the centromeres of the duplicated chromosome line up in the middle of the cell. The spindle fibers connect to each side of the centromere. Metaphase
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  During the thirdphase, the centromeres are pulled apart, and chromatids begin to separate into individual chromosomes. The chromosomes separate into two groups at opposite ends of the cell. Anaphase
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  During telophase, thefinal stage of mitosis, the chromosomes spread back out into a tangle of chromatin. The nucleus begins to reform around both sets of genetic material. The spindle breaks down during this stage. Telophase
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  Cytokinesis ● Cytokinesis isdivision of the cytoplasm. ● This is where the cell begins to physically separate into two. ● The cell membrane is drawn in until the cytoplasm is pinched in two. Note that this is NOT a part of mitosis. It is part of the M phase in the cell cycle, but cytokinesis is a separate but related process.
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  Cytokinesis in PlantCells Plant cells are not as flexible and easy to move as animal cells, so they have to perform cytokinesis a bit differently. Instead, a cell plate forms between the divided cells and then a cell wall forms in between the two new membranes.
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  When all issaid and done, the process should result in two genetically identical daughter cells. MEANING EACH CELL PRODUCED HAS THE SAME NUMBER OF CHROMOSOMES AS THE PARENT CELL End Result of Mitosis
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  Checkpoint! The main checkpoints occurat G1, G2, and during the Metaphase - Anaphase transition Just like in a video game, the cell cycle has different “checkpoints” If there is anything wrong with the cell (such as errors in DNA replication), the cell will not undergo mitosis.
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  Nothing is Perfect Justlike with most things in life, this process is not 100% foolproof. Sometimes things do go wrong with the checkpoints, and a damaged or diseased cell will be allowed to divide. Some types of diseases take advantage of this, and are caused by failures of the cell cycle checkpoints to regulate division.