1 1 Asexual Reproduction Mitosis Mitosis is the process in which the nucleus divides to form two new nuclei. After cytokinesis, 2 cells are formed that are identical to each other genetically, but 1/2 the size of the parent cell. How does mitosis differ in plants and animals?

How do little elephants grow up to be BIG elephants?

1. one parent  2. offspring identical to parent  3. occurs in unicellular organisms and body cells as a part of growth.

 A technique that accomplishes the same result as asexual reproduction. All offspring are identical to the parent because they carry the same genetic code as the parent.  plants - babies from spider plants are clones.  - stem rooted in water that becomes a plant is a clone.

 Done by removing a nucleus (with the genetic information) from a “parent” organism’s cell and inserting the nucleus into an egg cell from which the nucleus has been removed. The result is an egg that has 100% of the genetic information from a single parent. The egg cell is then implanted and develops inside of a female.  Cloning has been  accomplished in  sheep and pigs.

The process of asexual reproduction in us begins after a sperm fertilizes an egg.

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.

 Mitosis is the process by which a cell’s genetic material divides to create two sets of the cell’s genetic material. The product is two cells with a full set of identical genes and chromosomes, but the daughter cells are half the size of the parent cell. › Before mitosis can occur, the genetic information in the DNA of the parent cell is duplicated exactly. During cell division one copy is distributed to each cell. › Cytokinesis follows mitosis. In cytokinesis the cell divides the organelles and cytoplasm between the two new cells. 

Animated Mitosis Cycle Interphase Prophase Metaphase Anaphase Telophase & Cytokinesis

Chromosomes are copied Chromosomes appear as threadlike coils ( chromatin ) at the start, but each chromosome and its copy( sister chromosome) are called sister chromatids at end of this phase CELL MEMBRANE Nucleus Cytoplasm

One chromosome 2 sister chomatids Held by a centromere

Animal Cell Plant Cell Photographs from:

Centrioles (or poles) appear and begin to move to opposite end of the cell. Spindle fibers form between the poles. Chromosomes shorten and thicken Nuclear membrane and nucleoli disassemble Centrioles Sister chromatids Spindle fibers

Animal Cell Plant Cell Photographs from: Spindle fibers Centrioles

Chromatids (replicated chromosomes) attach to the spindle fibers at the centromere. Chromosomes line up at the equator Centrosome - Microtubule (spindle fibers) organizing center. Centrioles in Centrosome area Spindle fibers equator pole

Animal Cell Plant Cell Photographs from:

Chromatids (replicated chromosomes) separate and begin to move to opposite ends of the cell. Centrioles Spindle fibers

Animal Cell Plant Cell Photographs from:

Two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). Mitosis ends. Nuclei Chromatin

Animal CellPlant Cell Photographs from: Cleavage furrow Cell plate

Cell membrane moves inward to create two daughter cells – each with its own nucleus with identical chromosomes. Animals divide by a cleavage furrow and plants divide by building a cell plate

Animal Mitosis -- Review Interphase Prophase Metaphase Anaphase Telophase Interphase

Plant Mitosis -- Review Interphase Prophase Metaphase Anaphase Telophase Interphase

I I nterphase P P rophase M M etaphase A A naphase T T elophase C C ytokinesis IPMATC I Prefer Meat And Tasty Corn

Plant Cells Animal Cells Daughter cells contain the same Number of chromosomes as the parent cell ? No Centrioles Present, spindle forms ? ? Daughter cells have about half the cytoplasm of parent cell ? Centrosome is present Cytoplasmic division occurs by formation of a cell plate ?

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 11. What moves the chromatids during mitosis? ___________________________________  12. What anchors the spindle? ________________________________________  13. What are the four phases of mitosis? ___________________________________________________  14. How many daughter cells are created from mitosis and cytokinesis? ___________________________  15. During what phase does cytokinesis begin? ________________________________________  16. If a human cell has 46 chromosomes, how many chromosomes will be in each daughter cell? _________  17. If a dog cell has 72 chromosomes, how many daughter cells will be created during a single cell cycle? ______ .....Each of these daughter cells will have how many chromosomes? ____________  18. The nuclear membrane dissolves during what phase? ________________________  19. In the cell pictured above, how many chromosomes are present during prophase? ________________  20. What structure holds the individual chromatids together? ______________________________

 11. What moves the chromatids during mitosis? Spindle fibers  12. What anchors the spindle? centrioles  13. What are the four phases of mitosis? prophase, metaphase, anaphase, telophase  14. How many daughter cells are created from mitosis and cytokinesis? two  15. During what phase does cytokinesis begin? telophase  16. If a human cell has 46 chromosomes, how many chromosomes will be in each daughter cell? 46  17. If a dog cell has 72 chromosomes, how many daughter cells will be created during a single cell cycle? 2  Each of these daughter cells will have how many chromosomes? 72  18. The nuclear membrane dissolves during what phase? prophase  19. In the cell pictured above, how many chromosomes are present during prophase? 4  20. What structure holds the individual chromatids together? centromere