A BRIEF INTRODUCTION to

GENETICS

Honors GeneticsLemon Bay High SchoolMs. Susan Chabot

THE BEGINNING…• Domestication of plants

and animals inadvertently manipulated sexual reproduction.

• Preformation: Theory that a miniature human (homunculus) could be found inside the head of a sperm.

Paris, 1694

THE BEGINNING…Darwin and Evolution•1859: Origin of the Species•Ideas of natural selection supported hereditary passage of desirable/undesirable traits.

THE BEGINNING…• 1860’s: Gregor Mendel - an Austrian

monk grew peas in the monastery gardens.

• Noticed patterns among the generations of plants when they were cross-pollinated vs self-pollinated.

What We Know TodayEvery type of cell from every

kingdom contains DNA.

Sometimes the DNA is located in the NUCLEUS of the cell as in EUKARYOTES

Sometimes the DNA is NOT located in the NUCLEUS of the cell as in PROKARYOTES

Whether the organism is a EUKARYOTE or PROKARYOTE,

the DNA instructs the cell to make proteins.

The proteins are made into tissues , pigments, hormones, enzymes, and many other

components the cells need for survival.

Mitosis and HeLa

Visualizing Mitosis

Mistakes happenMutations

Cause mutations

Pesticides

Air pollution

Chemicals

Smoking

Radiation Sun

X-ray exposure

Fallout

Mutagens

•Recombinant DNA:

•Cutting the DNA from one organism and joining it with the DNA from another

•Human gene for insulin into bacteria: bacteria multiply and make insulin for diabetics

We Can Manipulate DNA

Insulin gene

Bacteria DNA

Dolly the sheep: insert the nucleus from the body cell of an adult sheep into the egg cell of another similar animal and allow to gestate.

CLONING:

Genetic Engineering

•Fertility:

• Inserting sperm nucleus into ovum to fertilize them for an infertile couple, then allow to gestate.

Genetic Engineering

Foods

•Insertion of pesticide genes into foods so that they will make proteins that will develop innate resistance to weeds and insects.

Genetic Engineering