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Asexual ReproductionThe production of a new organism without the fusion of two nuclei. The new organism develops FROM the cells of a single parent and has identical characteristics as the parent. This is very rapid and many offspring are produced.

Cell division consists of two processes:1. Nuclear Division

• This is called Mitosis or mitotic cell division• There is an exact duplication of a set of chromosomes creating

two identical sets. 2. Cytoplasmic Division

• This occurs during or after mitosis resulting in the formation of two daughter cells, each containing an identical set of chromosomes.

What is a chromosome? A thick threadlike structure that contains genetic information in the form of DNA.

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A Chromosome is a double strand of chromatid joined in the center by a centromere.

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MitosisIn Animals

•Prophase•Metaphase•Anaphase•Telophase

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Interphase•Not really a part of Mitosis (it happens before)•Lasts from the end of one cell division to the beginning of the next.•Known as the “resting period”

Prophase•Single stranded chromosome replicates into a double-stranded chromosome•Double stranded chromosomes are joined by centromeres.•Centrioles migrate to opposite ends (poles) of the cell forming spindle fibers.

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Metaphase•The double stranded chromosomes line up in the middle of each cell

Anaphase (think apart)•The double stranded chromosomes break at the centromere and divide into single-stranded daughter chromosomes•The daughter chromosomes then move apart to opposite poles with the aid of spindle fibers.

Telophase•Last stage of mitosis•Begins when chromosomes reach the poles•A nuclear membrane forms around each daughter cell•Cytokinesis divides the cell into two cells and the cytoplasm pinches in and identical two cells are made.

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Mitosis in plants

Plant cell division and animal cell division differ in two ways:

1. Plants do not have centrioles2. Plants have a rigid cell wall

which prevents the cell membrane from pinching in. Instead, a cell plate forms which divides the plant cell in half.

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Label the phases of Mitosis

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Types of Asexual Reproduction•Binary Fission

•Budding•Spore Formation

•Regeneration•Vegetative Propagation

(Binary Fission of Amoeba)

Binary Fission•Parent divides into two equal parts.•The two daughter cells are equal in size and grow to normal size.•Examples are Amoeba and Paramecium

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Budding•The Parent cell divides into two unequal parts.

•Yeast (unicellular) Two daughter cells are produced and one is larger than the

other.

•Hydra (multicellular)The daughter is a multicellular outgrowth of the parent, which budseparates from the parent.

(Yeast budding)

(Hydra budding)

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Sporulation•Many single celled reproductive cells are released into to environment •Under the right temperatures and moisture conditions these can develop into new individuals. •Examples are bread mold and mushrooms.

Regeneration•This is the development of a new organism from part of the original.•It can also mean the replacement of a body part.•A new starfish can develop from part of the parent.•A lobster can grow a new claw if one it torn off.•An earthworm can re-grow if one tip is cut off. •A salamander can also re-grow limbs

(blueberry)

(salamander)

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Vegetative Propagation

•The growing of new plants form parts of other plants.•Examples include:

Propagation Organism

cuttings (stem, leaf, root) geranium

bulbs onion, tulip

tubers potato

runners strawberry

grafting (joining of two parts) seedless orange or watermelon (any different version of a fruit)