The Cell Theory All cells come from other cells All living things are made up of at least one cell. Cells are the basic unit of structure and function in all living things.

The Cell Cycle

Cell Cycle All living things have a life cycle. Individual cells also have life cycles. Cell cycle is a series of events that takes place from one cell division to the next.

Why is cell division important? Many-celled organisms (like you) grow because cell division increases the total number of cells in an organism. One-celled organisms (bacteria, amoeba) use cell division to reproduce themselves.

Animated Cycle http://www.cellsalive.com/cell_cycle.htm

MITOSIS

Mitosis Definition: The process of cell division that results in the production of two new daughter cells. The daughter cells (containing the two new nuclei) are identical to one another and to the original parent cell.

Mitosis can be divided into stages interphase prophase metaphase anaphase telophase cytokinesis mitosis

Interphase This is not an actual step of mitosis Interphase This is not an actual step of mitosis! the cell prepares for division Animal Cell DNA replicated Organelles replicated Cell increases in size Plant Cell DNA replicated Organelles replicated Cell increases in size

Interphase Plant Cell Animal Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

Prophase the cell prepares for nuclear division Animal Cell Packages DNA into chromosomes Plant cell Packages DNA into chromosomes

Prophase Plant Cell Animal Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

Metaphase the cell prepares chromosomes for division Animal Cell Chromosomes line up at the middle of the cell Spindle fibers attach centrioles to chromosomes at the centromere Plant Cell Chromosomes line up at the center of the cell Spindle fibers attach centrioles to chromosomes at the centromere

Metaphase Plant Cell Animal Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

Anaphase the chromosomes divide Animal Cell Spindle fibers pull chromosomes apart One-half of each chromosome (called a chromotid) moves to each end of the cell Plant Cell Spindle fibers pull chromosomes apart One-half of each chromosome (called a chromotid) moves to each end of the cell

Anaphase Plant Cell Animal Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

Telophase new nuclear membranes form Animal Cell DNA spreads out, appears as chromatin (threads) 2 nuclei form with nuclear membrane Cell membrane pinches in to begin forming the two new daughter cells Plant Cell DNA spreads out, appears as chromatin (threads) 2 nuclei form with nuclear membrane New cell wall begins forming between the nuclei to begin forming the two new daughter cells

Telophase Plant Cell Animal Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

Cytokinesis the cytoplasm splits and the cell divides into two daughter cells each daughter cell has its own nucleus daughter cells have identical chromosomes in the nuclei http://www.bioweb.uncc.edu/biol1110/Stages.htm

Mitosis Animation http://www.cellsalive.com/mitosis.htm

Animal Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                             

Plant Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                             

Mitosis Animation http://www.brainpop.com/science/livingsystems/mitosis/