Science Starter Create a KWL chart on what you know, want to know, and want to learn about cellular reproduction Cell Cycle (Mitosis) SPI 0707.1.4 (Plant Cell Division) I can: Model the movement of chromosomes during plant cell division. Observation Activity You will be split into 10 groups At each station there is a booklet with a microscope slide inside a pouch You will first read the information in the booklet before you view the image in the microscope After you read the info and view the picture under the microscope, draw an image of what you see. Don’t forget to label your image with the correct phase of the cell cycle The slides are numbered, make sure your slide isn’t upside down when you view it or your images will be backwards Once you are done, place the microscope slide back in the booklet pouch Everyone is doing this on their OWN paper How do little elephants grow up to be BIG elephants? Why do animals shed their skin? Brain Pop As animals grow they pass through different stages in life. Cells, just like animals pass through different stages in their life cycle The life cycle of a cell is called the Cell Cycle • The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells • Before a cell divides it must make a copy of its DNA. • The DNA is organized into structures called chromosomes • Copying chromosomes ensures that each new cell will be an exact copy of its parent cell. Chromosome Structure Centromere-the point on a chromosome by which it is attached to a spindle fiber during cell division Centromere Chromosome Structure So 1 chromatid + 1 chromatid = 1 Chromosome 1 chromatid 1 chromatid Science Starter What are 3 reasons why cells reproduce ? Cell Cycle (Mitosis) SPI 0707.1.4 (Plant Cell Division) I can: Model the movement of chromosomes during plant cell division. Three reasons why cells reproduce by asexual reproduction: Skin cancer - the abnormal growth of skin cells - most often develops on skin exposed to the sun. Cell that reproduce by asexual reproduction reproduce constantly. 1. Growth 2. Repair 3.Replacement Chromosome Structure Centromere-the point on a chromosome by which it is attached to a spindle fiber during cell division Centromere Chromosome Structure So 1 chromatid + 1 chromatid = 1 Chromosome 1 chromatid 1 chromatid Cell Cycle 6 phases Interphase Prophase Metaphase Anaphase Telophase Cytokinesis Phases of Mitosis The Complete Cell Cycle Spot the differnce Interphase occurs before mitosis begins • • Chromosomes are copied (# doubles) Chromosomes appear as threadlike coils (chromatin) at the start, but each chromosome and its copy(sister chromosome) change to sister chromatids at end of this phase Nucleus CELL MEMBRANE Cytoplasm Interphase THE CELL: grows to it’s mature size Copy of its makes a _____ DNA Divide prepares to _______ into two cells Interphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Prophase 1st step in Mitosis • • • Mitosis begins (cell begins to divide) Centrioles (or poles) appear and begin to move to opposite end of the cell. Spindle fibers form between the poles. Sister chromatids Centrioles Spindle fibers Prophase the Chromatin condenses __________ (gets thicker) to form chromosomes, which are two chromatids attached by Centromere a ____________. Spindle fibers stretch out to _______ opposite ends of the cell the nucleus breaks down Prophase Animal Cell Plant Cell Spindle fibers Centrioles Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Metaphase 2nd step in Mitosis • Chromatids (or pairs of chromosomes) attach to the spindle fibers. Centrioles Spindle fibers Metaphase the Chromosomes __________ line up in the middle of the cell spindle fibers attach to Centromere of the the __________ chromosomes spot the difference Metaphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Anaphase 3rd step in Mitosis • Chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell. Centrioles Spindle fibers Anaphase Centromeres ____________ split and the chromatids separate chromatid to opposite ends of the cell being pulled by Spindle Fibers the ___________ the cell begins to become stretched out Anaphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Telophase 4th step in Mitosis • • • Two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). Mitosis ends. Nuclei Chroma tin Nuclei Telophase the __________ Nucleus reappears – two nuclei but one cell chromosomes begins to loosen up (start to become string again) A nuclear membrane appears around each set of chromosomes Telophase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Telophase Telophase is the last step of Mitosis but the cell cycle isn’t done just yet The next step is the division of the cytoplasm of the cell. This step is called Cytokinesis spot the differnce Cytokinesis occurs after mitosis • Cell membrane moves inward to create two daughter cells – each with its own nucleus with identical chromosomes. Cytokinesis the cell divides and two Daughter new ___________ cells are formed chromosomes loosen up and become chromatin again Animal Mitosis -- Review Interphase Prophase Metaphase Anaphase Telophase Interphase Plant Mitosis -- Review Interphase Prophase Metaphase Anaphase Telophase Interphase