3.4 Asexual Reproduction: Copies and Clones

Pages 94-98

Asexual Reproduction

roots or shoots develop into new plants (quick and easy)

budding (hydra, yeast) aphids females can give live birth to females Fragmentation: in fungi, parts break off and

grow

Cell Division

Mitosis: the genetic material in the nucleus of the parent cell is divided equally into two new nuclei.

Cytokinesis: the splitting of the cytoplasm and its contents into two new daughter cells.

Cell Cycle

Interphase

-cell growth and regular cell activitiesDNA is thread-like (chromatin)DNA replication-Sister chromatids remain attached at centromere…known as a chromosome

Prophase

-chromosomes shorten and thicken-centrioles separate and migrate to the poles-spindle fibres begin to form-nuclear membrane begins to dissolve

Metaphase

Spindle fibres work to align the chromosomes along the equatorial plate of the cell.

Anaphase

Centromeres divideChromosomes move to opposite sides of the cell

Telophase

Chromosomes begin to unwind.Spindle fibres dissolveNuclear membranes form around the nucleiPinching in of cell membrane in animal cellsCell Plate forms in plant cells

Cloning

producing a genetically-identical copy of a living organism

Animal Cloning

• Dolly the sheep• July 1996• Often do not live as long as normal individuals

and suffer from health problems.

Implications

Goodmass production of high quality plants and animals leads to high yields

Bad• possibly expensive to achieve• Some traits are detrimental• Loss of genetic diversity • Consumer dissatisfaction

GMO’s

• Genetically modified organisms• Genes from one species are added to the

genes of another species in order to improve it.

• Ex. Certain yeast and bacteria have an added human insulin gene added to their DNA.

GMO’s

• A goat that produces spider silk protein.• A banana that contains a vaccine.• A pig that produces healthy omega-3 fat.• Potatoes that make starch for biodegradeable

plastic.

Issues

• Moral• Ethical• Health concerns

Endangered species

• Potential to increase population.

Pet clones