copyright cmassengale Warm-up Question What are the three parts of the cell theory? copyright cmassengale
copyright cmassengale Cell Reproduction Prokaryotes Bacteria Eukaryotes Plants & animals copyright cmassengale
copyright cmassengale Prokaryotes Lack a nucleus Have a single chromosome Asexually reproduce by binary fission copyright cmassengale
Steps in Binary Fission Cells increase their cell mass. DNA is replicated Each cell divides into 2 daughter cells copyright cmassengale
Binary Fission of Bacterial Cell copyright cmassengale
E. Coli Dividing by Binary Fission copyright cmassengale
copyright cmassengale Eukaryotes Contain a nucleus & membrane bound organelles Asexually reproduce cells by mitosis copyright cmassengale
copyright cmassengale Cell Cycle Stages in growth & division are called the Cell Cycle. G1 Phase S Phase G2 Phase M Phase Cytokinesis copyright cmassengale
copyright cmassengale G1 Phase G1 = First growth stage What occurs during G1? Cell increases in size Cell prepares to copy its DNA copyright cmassengale
copyright cmassengale Synthesis Phase S = Synthesis Phase DNA’s instructions are copied in the S phase as chromosomes are duplicated. copyright cmassengale
copyright cmassengale G2 Phase G2 = Second growth stage. Time between DNA synthesis & mitosis. Cell continues to grow Makes proteins needed for mitosis or cell division. copyright cmassengale
copyright cmassengale M Phase M phase = Mitosis or Cell Division Cell’s energy used to make 2 daughter cells Cell growth & protein production stop Also called karyokinesis (nucleus division) copyright cmassengale
copyright cmassengale Life Cycle of a Cell Mitosis is a cycle with no beginning or end. copyright cmassengale
Interphase – Resting Stage What happens during interphase? Cells carrying on normal activities Cell metabolism is occurring Chromosomes aren’t visible during interphase copyright cmassengale
copyright cmassengale Interphase copyright cmassengale
copyright cmassengale Stages of Mitosis Prophase Metaphase Anaphase Telophase copyright cmassengale
Cells Undergoing Mitosis copyright cmassengale
copyright cmassengale Steps in Prophase DNA coils tightly Nuclear membrane disappears Nucleous disappears Centrioles migrate to poles Spindle begins to form ***Chromosomes can be seen during prophase! copyright cmassengale
copyright cmassengale Prophase copyright cmassengale
copyright cmassengale What is a chromosome? Chromosomes are made of DNA and protein. These structures contain the genetic material that is passed from generation to generation. Each chromosome contains 2 sister chromatids held together by a centromere. A kinetochore fiber attaches at the centromere to move the chromosome during mitosis. copyright cmassengale
Eukaryotic Chromosome copyright cmassengale
copyright cmassengale Steps in Metaphase Spindle fibers attach to each chromosome. Cell aligns its chromosomes in the middle of the cell Cell preparing to separate its chromosomes copyright cmassengale
copyright cmassengale Metaphase copyright cmassengale
copyright cmassengale Steps in Anaphase Cell chromosomes are separated Spindle fibers shorten so chromosomes pulled to ends of cell copyright cmassengale
copyright cmassengale Mitotic Spindle copyright cmassengale
copyright cmassengale Anaphase copyright cmassengale
copyright cmassengale Steps in Telophase Chromosomes are located at opposite ends of the cell. Nucleus & nucleolus reform Chromosomes uncoil Cell Plate forms (plants) Cleavage furrow forms(animals) copyright cmassengale
copyright cmassengale Telophase Plant Animal copyright cmassengale
copyright cmassengale Cytokinesis Cytokinesis = division of cytoplasm Occurs after mitosis Forms two, identical daughter cells copyright cmassengale
copyright cmassengale Cytokinesis Cell Plate Forming in Plant Cells copyright cmassengale
copyright cmassengale Mitosis Animation http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__mitosis_and_cytokinesis.html http://www.cellsalive.com/mitosis.htm copyright cmassengale