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Grade 9 Science Unit 2: Reproduction Chapter 5: “Mitosis is the basis of asexual reproduction.”
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Page 1: Chapter 5: “Mitosis is the basis of asexual reproduction.”

Grade 9 ScienceUnit 2: Reproduction

Chapter 5: “Mitosis is the basis of asexual

reproduction.”

Page 2: Chapter 5: “Mitosis is the basis of asexual reproduction.”

Complete Activity 5-1A

Page 3: Chapter 5: “Mitosis is the basis of asexual reproduction.”

Mitosis

The process in which the contents of a cell’s nucleus divide.

Results in two daughter cells identical to the parent.

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The double stranded chromosomes shorten and thicken.

The nuclear membrane begins to fade.

1. Prophase

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

2. Metaphase

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The chromatids are pulled to opposite poles of the cell.

3. Anaphase

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The nuclear membrane forms around each set of chromosomes.

The cell is ready to divide into two separate cells.

4. Telophase

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Animal cell

Plant cell

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Complete Activity 5-1C

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Only one parent is involved.

Offspring are identical to the parent.

Most reproduce quickly and in large numbers.

Asexual Reproduction

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1. Binary FissionA single parent cell replicates its genetic material and divides into two equal parts.

Types of Asexual Reproduction

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Amoeba

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Bacteria

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2. BuddingPart of the cell pushes outward to form an outgrowth or bud.

The bud pinches off to form the new offspring identical to parent.

Not all buds break away.

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yeast

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Hydra

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Sponge

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When an organism breaks apart as a result of injury, each fragment then develops into a clone of its parent.

3. Fragmentation

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Sea Stars

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Jap

an

ese

Kn

otw

eed

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4. Vegetative Reproduction

Occurs when special cells, in plants and roots, divide repeatedly to form structures that will eventually develop into plants identical to the parent.

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Potato Sprouts

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Strawberry Runners

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Tulip Bulbs

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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.

5. Spore Formation

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Bread Mold Spores

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Puffball

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Summary of Asexual Reproduction…

AdvantagesLarge # of offspring are produced quickly.

Large colonies can form to out-compete.

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Large # of offspring mean the species may survive when conditions change

Energy is not required to find a mate.

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Disadvantages

Offspring are genetic clones.

Negative mutations can destroy large #s.

Those produced close together must compete.

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Unfavorable conditions can wipe out entire colonies.

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“Determining the Best Conditions for Yeast

Reproduction”

Core Lab Activity 5-2B Pg. 162-4