Mitosis is the Basis of Asexual Reproduction Chapter 5 Mitosis is the Basis of Asexual Reproduction

Section 5.1: Mitosis Page 142

Mitosis page 142 The Process by which the content in a cell’s nucleus divides Results in 2 daughter cells nuclei each with the same number and kinds of chromosomes as the parent cell “Marathon” writing activity suggested to tap into what students know about how cells are involved in growth and reproduction. Instruct that all cells except the gametes use mitosis for growth and or cell replacement. Not all have the same rate of cell reproduction, skin cells renew every 15-30 days. Stomach lining cells about 2 days, red blood cells about 120 days, brain cells 30-50 years and do not renew! Liver cells about 200 days

Activity 5-1A From one Cell to Many Cells Page 138 Use Blackline Masters and Use for Evaluation Ask the question wether they would rather have 1 million dollars or the amount of money you would have if you place a penny on a chess board and doubled the amount every block (64 blocks) would result in approximately 9.2 x 1018 pennies, at 30 there would be 536870912, over taking a million at block 28! Activity 5-1A From one Cell to Many Cells Page 138

Prophase Metaphase Anaphase Telophase Stages of Mitosis Use Blackline Master 2-10 for simple note taking, could Include Flip book activity or worksheets form 3D posters information

PROPHASE The double stranded chromosomes (DNA) shorten and thicken The nuclear membrane begins to fade.

METAPHASE X-shaped chromosomes are pulled into a single line across the middle of the cell.

ANAPHASE The x-shaped sister chromatids are pulled to opposite poles of the cell.

TELOPHASE The nuclear membrane forms around each set of chromosomes. The cell is ready to divide into 2 separate cells. Have students reinact the process of mitosis acording to guided activity provided. Also could do a choice of assignment porfolio ideas including a mitosis flip book or creating a poster with string or pipe cleaners or other representation they prefer. Have students look at

Cytokinesis: The phase in the life cycle of a cell which separates the 2 cell nuclei and contents into 2 daughter cells after mitosis. Interactive web-site www.cellsalive.com

Activity 5-1C Observing the Cell Cycle in Plant Cells Page 148 Include Media presentations of Mitosis and stages as well as have the students look through a microscope. Activity to compare websites provided. State DNA is not visible in a cell unless it is undergoing division. Check Your Understanding Questions page 151 #2-7 Activity 5-1C Observing the Cell Cycle in Plant Cells Page 148

Section 5.2: Asexual Reproduction Page 152

ASEXUAL REPRODUCTION Only 1 parent is involved. Offspring are identical to the parent. Most reproduce quickly and in LARGE numbers.

Types of Asexual Reproduction: Binary fission Budding Fragmentation Vegetative reproduction Spore formation

1. Binary Fission A single parent cell replicates its genetic material and divides into 2 equal parts. Ex: amoeba bacteria

2. Fragmentation When an organism breaks apart as a result of injury, each fragment then develops into a clone of its parent. Ex: starfish Japanese knotweed

3. Budding Part of the cell pushes outward to form an outgrowth or bud. The bud pinches off to form the new offspring identical to parent. Ex: yeast hydra sponge

4. Vegetative Reproduction Ex: bulbs sprouts runners (tulip) (potato) (strawberry) Occurs when special cells, in plants and roots, divide repeatedly to form structures that will eventually develop into plants identical to the parent.

5. Spore Formation A spore is a reproductive cell that grows into a new individual by mitosis. Light in weight. Rely on water, or wind to carry spores away from parent plant. Bread mould

ASEXUAL REPRODUCTION Offspring are genetic clones ADVANTAGES DISADVANTAGES Produces large numbers quickly Large populations mean some may survive if environmental conditions change Energy is not required to find a mate Offspring are genetic clones Negative mutations can destroy entire populations Populations close together must compete Unfavourable conditions can wipe out entire populations Use a fishbone diagram to distinguish + and – of asexual reproduction

Set Questions page 165 #1,5,6,7,8,11,13,14 Chapter Review page 166, could use fish bone illustrated. #1,2,6,12,13,14,15,16, Also Pause and Reflect – Are offspring that are produced through asexual reproduction always identical to their parents? CORE LAB Acitivty 5-2B Determining the Best Conditions for Yeast Reproduction Page 162