Interphase Mitosis Cytokinesis The Cell Cycle Interphase Mitosis Cytokinesis

How do little elephants grow up to be BIG elephants?

Why do animals shed their skin?

How does the cell know how to divide? Cell Division Reproduction Growth Repair Why do cells divide? How does the cell know how to divide? The DNA has the instructions for all of the cell’s activities.

Cell Cycle 3 Parts The sequence of development and division of a cell Interphase - Preparation Mitosis – Cell division Cytokinesis – Splitting Adult human cell: ~24 hrs 18-20 hours in interphase 2 hours in mitosis How long does it take?

Animated Cell Cycle Interphase Prophase Metaphase Anaphase Telophase http://www.cellsalive.com/mitosis.htm Interphase Prophase Metaphase Anaphase Telophase Cytokinesis

occurs before mitosis begins Interphase occurs before mitosis begins What happens Centrioles Cell in Resting State When ready to divide, Cell doubles in size DNA replicates or copies itself Organelles double in number DNA condenses into chromatin, a thread like coil Nucleolus Chromatin Cell Membrane

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

Number of Chromosomes in Different Species Dog - 76 Rat – 92 Bean – 22 Human – 46 Elephant – 56 Cow – 60 Fly 8 Chimp - 48

Mitosis: 1st PROPHASE What happens Chromosome Chromatin (DNA) forms into 2 sister chromatids that make up 1 chromosome = Chromosomes Form Spindle fibers form Centrioles move toward opposite ends of the cell Nuclear membrane begins to disappear Nucleolus disappears Centromere 2 Sister Chromatids

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

Mitosis: 2nd METAPHASE What happens Nucleus has disappeared completely Spindle Fibers attach to centromeres Chromosomes line up in the middle of the cell Chromatid 1A Centrioles Chromosome 1 Chromatid 1B

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

Mitosis: 3rd ANAPHASE What happens Centromeres divide Chromatid What happens Centromeres divide Spindle Fibers pull chromatids away towards opposite poles Chromosomes are separated Centrioles Spindle Fibers

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

Mitosis: TELOPHASE What happens Nuclear membrane forms around each group of chromosomes Chromosomes unwind into chromatin Cytokinesis begins Centrioles Cell begins to separate

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

Cytokinesis What happens Chromatin returns to DNA 2 Identical Cells Chromatin returns to DNA Cytoplasm and organelles divide into each cell One cell becomes 2 cells What happens

Final Product Mitosis produces 2 daughter cells genetically identical to each other and the original parent cell.

Animal Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                             

Plant Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                             

IPMATC REMEMBER! Interphase Prophase Metaphase Anaphase Telophase Cytokinesis IPMATC A mnemonic to help remember the stages of mitosis. I Play More At The Circus

Cell Cycle