human physiology

Essential question: How have humans used technologies to influence the inheritance of desired traits in organisms?

• Genetic Modification
• GM stands for ‘genetically-modified‘
• describes the process by which scientists are able to pinpoint the individual gene
• Remove gene, copy it, place it in new organism
• produces a desired outcome
• Selective Breeding
• theintentional mating of two animals or plants
• producesoffspring with desirable traits
• Can also get rid of unwanted traits
• Animal Husbandry

• Selective Breeding of animals only
• Concerned with the production and care of domestic animals
• Gene Therapy
• Technique that uses genes to treat or prevent disease.
• May allow doctors to treat a disorder by putting a gene into a patient’s cells
• No need for drugs or surgery.

GENETICALLY MODIFIED ORGANSIMS

Reasons for Genetically Modifying Organisms

• Produce faster growing crops or animals
• Produce plants that are more resistant to pests
• Produce crops that are drought resistant
• Produce foods that stay ripe longer

• Increase yield of crop
• Reduce cost that is passed to consumer
• Enhance the nutritional value of a food

• The first GMOs were bacteria in the early 1970s.
• Most basic modifications are designed and prepared using bacteria (usually E.Coli) and then transferred to the target organisms.

Controversy of Genetically modified organisms

• Controversy over GMOs in general:
• Genetic modification is placing the genes of one species into another unrelated species.
• Some modifications are created by corporations to make crops resistant to pests or to certain chemicals.
• Controversy over GM foods:
• Have they been tested enough to prove they are safe?
• Could pesticide resistant plants become toxic?
• Could peanut genes inserted into soybeans cause unexpected allergic reactions?

• What evidence is there of problems with GM crops?
• Some studies have shown negative results for lab animals that ate GMO foods.
• Those foods were not meant for human consumption
• There are not very many studies that show these negative results.
• Other scientists have criticized and questioned some of these studies.

Pros and cons of GMO Food

• Pros
• Higher crop yields
• Reduced need for herbicides and pesticides
• Improved food quality
• Increased nutritional value

• Cons
• Possible allergies
• Unpredicted changes to the ecosystem
• Chance of new diseases developing

SELECTIVE BREEDING  AND  ANIMAL HUSBANDRY

• Improve food production
• Better able to fight off pests
• More fit and stronger animals
• Cows that give more milk
• Chickens that lay bigger eggs
• Selective Breeding – Plants and Animals
• Animal Husbandry – Animals only
• Typically for farming and agriculture

Process of Selective Breeding

• Decide which characteristics are important
• Choose parents that show these characteristics
• Select the best offspring from parents to breed the next generation
• Repeat the process continuously
• Human controlled Natural Selection/Evolution

Controversies of Selective breeding

• Animal Rights:
• Should animals have the right to select their own breeding partners?
• Unnatural
• It doesn’t occur in nature, does that make it wrong?

• Benefits to humanity
• Better/more plentiful food.
• Service animals
• Humans have been using selective breeding for thousands of years already.

GENE THERAPY

REASONS FOR GENE THERAPY

• To alter genes to correct genetic defects
• prevent or cure genetic diseases.
• Not to be confused with Genetic engineering which changes the genes to make the organism better than normal.
• Possibility to cure deadly diseases like cancer

Process of Gene Therapy

Three different ways:

• Replacing a mutated gene that causes disease with a healthy copy of the gene
• Inactivating, or “knocking out,” a mutated gene that is functioning improperly
• Introducing a new gene into the body to help fight a disease

Controversies of Gene Therapy

• Pros:
• Could wipe out genetic diseases
• Prevent genetic disorders in future generations for families who know they have it in their bloodline

• Cons:
• Still a dangerous and difficult process
• When used in unborn children, not sure of effects
• Child doesn’t have a choice