1 1 Mitosis BODY Cell Division (Chapter 3 : 3 p.86-89)  Mitosis is the process in which the nucleus divides to form two new nuclei.  Mitosis differs in plants and animals.  A form of asexual reproduction – one cell divides into two

How do little elephants grow up to be BIG elephants?

Skin cancer - the abnormal growth of skin cells - most often develops on skin exposed to the sun.

Cells that reproduce by asexual reproduction reproduce constantly.

Animated Mitosis Cycle Interphase Prophase Metaphase Anaphase Telophase & Cytokinesis

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 CELL MEMBRANE Nucleus Cytoplasm

Animal Cell Plant Cell

Mitosis begins (cell begins to divide) Centrioles appear and begin to move to opposite end of the cell. Spindle fibers form between the centrioles. Centrioles Sister chromatids Spindle fibers

Animal Cell Plant Cell Spindle fibers Centrioles

Chromatids (or pairs of chromosomes held together by centromeres) meet in the middle of the cell and attach to the spindle fibers. Centrioles Spindle fibers

Animal Cell Plant Cell

The centromere splits and the sister chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell. The separated chromatids are now called chromosomes. Centrioles Spindle fibers

Animal Cell Plant Cell

A new nucleus forms around each identical groups of chromosomes at opposite sides of the cell and two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). The cell membrane starts to move inward near the middle of the cell. Mitosis ends. Nuclei Chromatin

Animal Cell Plant Cell

The cytoplasm is completely pinched creating two identical daughter cells – each with its own nucleus with identical chromosomes.

Animal Mitosis -- Review Interphase 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase Cytokinesis

Plant Mitosis -- Review Interphase 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase Cytokinesis

Cell plate

I I nterphase P P rophase M M etaphase A A naphase T T elophase C C ytokinesis IPMATC I Pray M ore At T he Church

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