Asexual Reproduction presents: Mrs. Stewart Honors Biology: Cell Growth and Division 1 1 1

MITOSIS A CELL GROWTH AND DIVISION PRODUCTION 11/01/11

How do little elephants grow up to be BIG elephants? BELL WORK How do little elephants grow up to be BIG elephants?

Are the cells of the adult elephant larger than those of the baby? BELL WORK Are the cells of the adult elephant larger than those of the baby?

standards CLE 3210.4.2 Describe the relationships among genes, chromosomes, proteins, and hereditary traits. 11/01/11

Objectives Evaluate the reasons for asexual reproduction in organisms Differentiate between the different stages of the cell cycle in terms of order of occurrence, and chromosome location 11/01/11

Let’s review: Chromosomes What do they look like? How many do humans have? They look like an “X” just before the cell divides and an “I” after they divide. 46 (23 pairs) (23 from mom, 23 from dad)

Cell Division in eukaryotes There are two different types of cell division Which type is performed depends on the kind of “daughter cells” that are desired Meiosis = genetically different daughter cells with half the amount of DNA Mitosis = identical daughter cells with same amount of DNA 11/01/11

Somatic Cells Gamete Every cell in the body EXCEPT reproductive cells Have all 46 chromosomes Gamete Sexual reproduction cells (Example: sperm for males, Ova/eggs for females) have half the amount DNA (23 chromosomes) 11/01/11

Which cells do Mitosis? Somatic OR Gametes 11/01/11

Why do animals shed their skin? THINK – PAIR - SHARE 11/01/11

How does a cut heal? THINK – PAIR - SHARE 11/01/11

Asexual reproduction - Requires only ONE parent/cell - Makes Somatic cells Three reasons why cells reproduce by asexual reproduction: 1. Growth 2. Repair 3. Replacement 11/01/11

At what point does it become necessary for a cell to divide? When the cells resources are under too great a strain from it’s size Cell Membrane not large enough to maintain needs coming in/going out DNA, used for protein synthesis, cant keep up with demands Organelles unable to keep up with demands (ie: waste removal) 11/01/11

Cell Cycle 2 Main Stages: Interphase G1 S G2 Mitosis – M phase Prophase Metaphase Anaphase Telophase Cytokinesis Cell Cycle 11/01/11

Which phase does the cell spend the most time in? Interphase 11/01/11

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Create your graphic organizer CELL CYCLE INTERPHASE ANAPHASE PROPHASE TELOPHASE METAPHASE CYTOKINESIS Create your graphic organizer 11/01/11

I-P-M-A-T-C Assignment: Create a mnemonic device to help you remember – I-P-M-A-T-C We will vote on the best one tomorrow in class. Winner gets a two day “slack” pass. 11/01/11

animation Mitosis animation – mcgraw-hill Cell cycle animation – cells alive website Mitosis – sumanas (step by step w/ tutorial and quiz) 11/01/11

Interphase 3 phases: G1: Growth and everyday activities Time between cell divisions 90% of a cell’s life 3 phases: G1: Growth and everyday activities S: DNA replication G2: preparation for Mitosis (production of necessary proteins/organelles) Interphase 11/01/11

The process of dividing the nucleus to create two daughter cells, identical to the mother cell Mitosis

Mitosis Creates two daughter cells that are identical to each other AND identical to the parent cell Creates diploid cells (two sets of chromosomes in each daughter cell) Allows organisms to grow Allows organisms to replace damaged/worn out cells P-M-A-T-C 11/01/11

The DNA (chromatin) organizes into chromosomes The nuclear membrane disappears Centrosomes (centrioles) move to opposite ends of cell PROPHASE 11/01/11

Chromosomes attach to spindle fibers (by their centromeres), and line up at the center of the cell METAPHASE Spindle Fibers – microtubules that help separate chromosomes during division 11/01/11

Chromosomes separate at the centromere, and the sister chromatids are pulled toward opposite ends of the cell. ANAPHASE 11/01/11

Chromosomes disorganize and the nuclear membrane begins to reform. TELOPHASE 11/01/11

The division of the cell cytoplasm, usually beginning during Telophase and finalizing the production of two new daughter cells. Each new cell will have about ½ of the cytoplasm and organelles of the parent cell. CYTOKINESIS 11/01/11

Cleavage furrow indentation of the cell membrane to form two separate VS. CELL PLATE Plants Cell plate A cell wall is rigid and cannot flexibly move and pinch together to separate the newly formed cells. So, a cell plate forms between the two new cells. This cell plate will harden and become a cell wall for each. ANIMAL Cleavage furrow indentation of the cell membrane to form two separate cells CYTOKINESIS 11/01/11

CLEAVAGE FURROW VS. CELL PLATE 11/01/11

REMEMBER: I P M A T C Interphase Prophase Metaphase Anaphase Telophase Cytokinesis I PLAY MUSIC AT THE CLUB I P M A T C 11/01/11

Create your post-it note paper Musical chairs Students are each given 6 post it notes and told to write the names of the stages of the cell cycle on them. Then they are told to put those stages in order (IPMATC). Then, they must mix them up. At that point, turn on some music and have the students move around the room. When the music stops, the students must stay at the closest desk and put the post it notes back in order. Have students chant the stages of the cell cycle as a class. Mix up the post-its again and repeat musical chairs. 11/01/11

Animal Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                              Cytokinesis                                                              Animal Mitosis -- Review

Plant Mitosis -- Review Interphase                                                              Prophase                                                              Metaphase                                                              Anaphase                                                              Telophase                                                              Cytokinesis                                                              Plant Mitosis -- Review

Identify the following: Structure X Structure Y Reflection: Y Identify the following: Structure X Structure Y Which stage of the cell cycle is shown? 11/01/11