Transcript Slide 1
Warm-up Reflecting on the Genetics Unit, draw one of the following: 1. A Venn Diagram of Mitosis and Meiosis 2. A flow-chart describing the steps of recombinant DNA technology Chimera: An organism or tissue created by 2 different genetic sources Selective Breeding Is there a risk to this? Inbreeding Decreasing Variation: Inbreeding • What is the benefit of inbreeding? Desirable Traits • What is a possible risk of inbreeding? Harmful recessive alleles for genetic defects are expressed Hybridization ♀ ♂ 2n=22 Donkey 4n=44 Horse 2n=22 2n = 64, n = 32 n=11 2n = 62, n = 31 3n=33 1 Mule Can this be divided to make 2n = gametes? 63, n = ? F Increasing Variation: Mutagens Breeders can increase genetic variation by inducing mutations. What are some ways one can induce a mutation? Radiation Chemicals Tools of Molecular Biology 1. DNA Extraction 2. Cutting DNA – Restriction Enzymes 3. Separating DNA – Gel Electrophoresis Restriction Enzymes Recognition Sequences DNA Sequence EcoRI cuts the DNA into fragments These are sticky ends Polymerase Chain Reaction • How many copies of DNA will there be after six cycles? 32 copies • After about 30 cycles? Over 1 billion! Transforming Plant Cells Using your knowledge of plants, what might be a challenge to a scientist trying to get foreign DNA into a plant cell? The plant cell wall! Transforming Animal Cells • What animal cells are often used in the transformation process? Egg Cells Transgenic Organisms An enzyme from fireflies causes this tobacco plant to glow Transgenic Animals • Mice are used to study human disease • Livestock have growth hormones • Chicken will be genetically modified to resist bacterial infection Transgenic Plants • Insect and weed resistance can be transgenically induced in plants • Vitamin A can be added to rice for nourishing third world countries