Changing the Living World
Selective breeding
Breeding animals with characteristics we want to produce offspring with those
Plants – Potatoes or flowers
Animals – dogs or farm animals
Changing the Living World
 Hybridization
Cross different individuals to get offspring with favorable traits
The result is a hybrid – an individual produced from the crossing of two different organisms.
Changing the Living World
 Inbreeding
Breed similar individuals over and over to get offspring with favorable traits
Changing the Living World
Increasing variation
Inducing mutations
Radiation
Chemicals
Produce mutants – an individual showing the mutation
Changing the Living World
Producing new bacteria
Small size allows for millions to be treated
Oil eating bacteria
Changing the Living World
Producing new plants
Chemicals that prevent chromosomal separation
Polypoidy
Larger and stronger plants
13-2 Manipulating DNA
How can scientists manipulate the code?
Scientists use their knowledge of the structure of DNA and its chemical properties to study and change DNA molecules.
13-2 Manipulating DNA
Tools of Molecular Biology
Genetic Engineering
Making changes in the DNA code of a living organism
DNA Extraction
Open a cell (mechanical and chemical methods)
Use a chemical to separate the DNA from the rest of the cell parts (an alcohol)
13-2 Manipulating DNA
Cutting DNA
DNA molecules are very long
Restriction enzymes
Enzymes that cuts DNA at a specific sequence of nucleotides
Sticky ends – these are the cut ends of the DNA