Mitosis Meiosis Mitosis animation http www youtube comwatch

Mitosis & Meiosis Mitosis animation: http: //www. youtube. com/watch? v=2 Ww. IKdy. BN_s&feature=related

Mitosis: n n If a cell wants to make a duplicate of itself, it first must copy its DNA (part of a chromosome). The copies then must be separated & sorted into two sides of the cell. The cell then splits in two. Part of each parent is carried to the two new cells. Results in cells such as internal organs, skin, bones, blood, etc.

Meiosis: n As in mitosis, if a cell wants to make a duplicate of itself, it first must copy its DNA (part of a chromosome). n Results in reproductive cells (sperm, eggs, etc). n Part of each parent is carried to the four new cells. n Meiosis has evolved to solve a problem. n The problem is this: some organisms have sex with other organisms – that is, they combine their genes together (creating genetic diversity). n Why would this be a problem?

This may you remember these terms: n MITosis takes the cell and Makes It Two (diploid) n Meiosis has to do with sex n From the cell’s point of view: n m. ITosis results in Identical Twins n m. Eio. Sis results in Egg and Sperm (haploid) Clyde Freeman Herreid – Dept. of Biological Sciences: Buffalo State Univ. of New York

Mitosis: Meiosis: Each resulting cell still has chromosomes from mom & dad

Mitosis n Mitosis animations: n http: //www. youtube. com/watch? v=2 Ww. IKdy. BN_s&feature=related n http: //www. youtube. com/watch? v=Vl. N 7 K 1 -9 QB 0

Interphase occurs just before Mitosis begins: DNA is replicated along with organelles and other cellular components and the cell prepares for division. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm

Mitosis Interphase Animal cell Plant cell Photographs from: http: //www. bioweb. uncc. edu/biol 1110/Stages. htm

st 1 step in Mitosis: Prophase (preparation phase) The DNA recoils, and the chromosomes condense; the nuclear membrane disappears, and the mitotic spindles begin to form. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm

Mitosis Prophase Animal cell Plant cell Photographs from: http: //www. bioweb. uncc. edu/biol 1110/Stages. htm

2 nd step in Mitosis: metaphase (organizational phase) The chromosomes line up the middle of the cell with the help of spindle fibers attached to the centromere of each replicated chromosome. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm

Mitosis Metaphase Animal cell Plant cell Photographs from: http: //www. bioweb. uncc. edu/biol 1110/Stages. htm

rd 3 step in Mitosis: Anaphase (separation phase) The chromosomes split in the middle and the sister chromatids are pulled by the spindle fibers to opposite poles of the cell. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm

Mitosis Anaphase Animal cell Plant cell Photographs from: http: //www. bioweb. uncc. edu/biol 1110/Stages. htm

th 4 step in Mitosis: Telophase The chromosomes, along with the cytoplasm and its organelles and membranes are divided into 2 portions. This diagram shows the end of telophase. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm

Mitosis Telophase Animal cell Plant cell Photographs from: http: //www. bioweb. uncc. edu/biol 1110/Stages. htm

After Mitosis: Cytokinesis Beginning of cytokinesis in a plant: The actual splitting of the daughter cells into two separate cells is called cytokinesis and occurs differently in both plant and animal Cells. http: //www. bioweb. uncc. edu/1110 Lab/notes 1/lab 6. htm Beginning of cytokinesis in an animal:

Meiosis n Meiosis animation: http: //www. youtube. com/watch? v=D 1_-m. QS_FZ 0&NR=1

Meiosis Interphase Meiosis is preceded by interphase. The chromosomes have not yet condensed. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Interphase The chromosomes have replicated, and the chromatin begins to condense. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Prophase I The chromosomes are completely condensed. In meiosis (unlike mitosis), the homologous chromosomes pair with one another http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Metaphase I The nuclear membrane dissolves and the homologous chromosomes attach to the spindle fibers. They are preparing to go to opposite poles. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Anaphase I The chromosomes move to opposite ends of the cell. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Telophase I & Cytokinesis The cell begins to divide into two daughter cells. It is important to understand that each daughter cell can get any combination of maternal and paternal chromosomes. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Prophase II The cell has divided into two daughter cells. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Metaphase II As in Meiosis I, the chromosomes line up on the spindle fibers. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Meiosis Anaphase II The two cells each begin to divide. As in Meiosis I, the chromosomes move to opposite ends of each cell. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Telophase II & Cytokinesis With the formation of four cells, meiosis is over. Each of these prospective germ cells carries half the number of chromosomes of somatic cells. http: //morgan. rutgers. edu/Morgan. Web. Frames/Level 1/Page 7/meiosis 1. html

Results of Mitosis First, it is the division of a nucleus Second, it produces two nuclei that are identical to each other and the original nucleus Each new nucleus has the same number and type of chromosomes

n Every cell in your body, except sex cells, has a nucleus with 46 chromosomes- 23 pairs n Each of the trillions cells in your body, except sex cells, has a copy of the same hereditary material

n Cell division allows growth and replaces worn out or damaged cells n If you cut yourself, the wound heals because cell division replaces damaged cells. n Another way some organisms use cell division is to produce new organisms

Reproduction n Reproduction is the process by which an organism produces others of its same kind n Among living organisms, there are two types of reproduction- sexual and asexual

Asexual Reproduction n A new organism, sometimes more than one, is produced from one organism n The new organism will have hereditary material identical to the hereditary material of the parent organism

Cellular Asexual Reproduction n n Organisms with eukaryotic cells asexually reproduce by cell division. A sweet potato growing in a jar of water is an example of asexual reproduction Recall that mitosis is the division of a nucleus. Bacteria does not have a nucleus so they can’t use mitosis

Budding and Regeneration n A new organism is growing from the body of the parent organism Budding is a type of asexual reproduction made possible because of cell division. Some organisms can regrow damaged or lost body parts

Regeneration n n Regeneration is the process that uses cell division to regrow body parts Sponges, planaria, sea stars and some other organisms can use regeneration for asexual reproduction

Sexual Reproduction n Another way that a new organism can be produced, Two sex cells, an egg and a sperm, come together Sex cells are formed from cells in reproductive organs

Fertilization n The joining of the egg and sperm…. the cell forms a zygote Generally, the egg and sperm come from two different organisms of the same species Following fertilization, cell division begins

Vocabulary for this section n n n Diploid Haploid DNA Genome Gene Nucleus Organelle Nuclear envelope Cytoplasm Asexual reproduction Sexual reproduction Fission Cell division n n n Cell Organism Replication Cancer Cell cycle Phase Reproduction Offspring Meiosis Mitosis Regeneration Budding spore