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Genetic Engineering. SELECTIVE BREEDING (Hybridization vs. Inbreeding; biotechnology). Selective Breeding. Hunters in the 1800 ’ s needed a hunting dog that was big, strong, fast, and aggressive However, no dog like this existed at that time
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Genetic Engineering SELECTIVE BREEDING (Hybridization vs. Inbreeding; biotechnology)
Selective Breeding • Hunters in the 1800’s needed a hunting dog that was big, strong, fast, and aggressive • However, no dog like this existed at that time • They knew of two species of dogs, each with some of the desired qualities • Can they somehow combine the two into one?
American Bulldog Mastiff Fast and aggressive, but lacked size Big and strong, but lacked speed and aggression Big, strong, fast, and aggressive Bullmastiff
Why use selective breeding? • Humans use selective breeding, which takes advantage of naturally occurring genetic variation, to pass wanted traits on to the next generation of organisms • What ways can humans selectively breed plants or animals?
The Great Famine killed millions of people in Ireland that depended on Irish potatoes as a staple to get them through the winter. Luther Burbank developed a new Irish potato that did not get blight. This potato Was sent to Ireland. Irish Potato Famine 1845-1851
2 Types of Selective Breeding Hybridization Inbreeding Crossing breeds of individuals with similar characteristics Maintains traits of that breed (purebreds) Risky – increases chance for mutation since individuals are very genetically similar to each other • Crossing dissimilar individuals to bring together the best of both worlds • American botanist Luther Burbank selectively bred 800 plants, called varieties • Many varieties can be found in your supermarket! • Bred for size, disease resistance, flowering, taste, color and a variety of other reasons based on preference
Place in notes! 1. List the 2 types of selective breeding. • Who was Luther Burbank? How did he help Ireland using selective breeding? • Define polyploid plants- • Why are polyploid plants desirable in the florist business and farming? • Why would polyploid, extra numbers of chromosomes, not work in animals?
Inbreeding • Inbreeding uses two genetically similar organisms, each being “the best of the best” • Dog breeds are maintained by inbreeding • Characteristics that are unique to each breed are preserved • Very prevalent in cattle farming – gives farmers the best possible livestock • Also can be very dangerous if two individuals have an underlying mutation
Designer Doggies • Aussiedoodle • Australian shepherd xPoodle • Cavapoo • Cavalier King Charles xPoodle • Cheagle • Chihuahua xBeagle
Problems with Inbreeding in Dogs List 4 problems Associated with Inbreeding dogs. (Place in your notes)
Inbreeding Problems List 3 additional Problems that can Happen due to Inbreeding in dogs. (Place in notes!)
Hybridization • Hybridization occurs in both plants and animals • Creating hybrid plants is different than creating hybrid animals • Animals can be sterile if their chromosome number is odd, or if there are too many mutations that occur when they breed naturally (rarely occurs in the wild) • Plants can be bred easily by gardeners or botanists • Many crops today are hybrids (can sometimes occur naturally in the wild)
List 4 characteristics of hybridized plants (Place in notes!)
Genetically-Engineered Hybrid Plants(List 4 ex. of GE Plants in notes) • You have probably eaten many GE plants without realizing it. Examples include: • Seedless grapes/ watermelons • Bananas, which commonly have polyploidy (extra sets of chromosomes – stronger, bigger) • Corn – modern corn wasselectively bred from teosinte at least 6,000 years ago
Can you guess these hybrid fruits? • Limequats • Lime x Kumquat • Tangelo • Tangerine x Pomelo
Pineberries look like smallish strawberries in size and shape, but are white in color and studded with red seeds. They taste and smell like pineapples but have the same genetic makeup as a strawberry. They are a product of cross-breeding, not genetic engineering
Hybridization • Hybridized animals are called hybrids • Can you identify these hybrids? Why would a farmer what to breed a buffalo and a cow?
Horse + Donkey=Mule (sterile) Why are mules so desirable as work animals?
Canis lupus (gray wolf) Canis latrans (coyote) Canis rufus (red wolf) Canis familiaries (dog)
Sheep + goat = geep What purpose Do these hybrid Animals serve? Are they sterile? Horse + zebra=Zorse (sterile)
Induced Mutation • How? Chemicals and Radiation • Why? Increase Variation (Place in notes!)
List 4 ways plants (crops) can be modified. (Place in notes!)
Gel Electro/phore/sis • What role does the gel play in gel electrophoresis? • What role does the electro (electricity) play in this process? • What role does the phore (pores) play in gel electrophoresis? • Give another name for gel electrophoresis.
What is the name of the • enzyme responsible for • cutting the DNA into • fragments? • Are all the DNA fragments • the same length? • What pushes the DNA fragments • through the gel? • Which DNA fragment (short • or long) do you think would • move through the gel faster?
How did the mixture of DNA get to so many different sizes? • Is DNA a positive or negative charged molecule? • The starting line, so to speak, is at the wells. Can you identify • the wells? • The DNA fragments of different sizes migrate toward the ____ • end. • 5. Are the fragments shorter or longer near the wells? At the end?
How many lanes do you see? Can you identify the top from the bottom? The fragments at the top are they longer or shorter than at the bottom?
*What does the 70, 60, 50, etc. mean? *What do you thing Std. stands for above lane 1? How about CS1 and CS2? *Who was at the crime scenes? Can you identify which suspect was at the crime scene?
Remember a child is made up of _____% of mom’s DNA • and _____% of dad’s DNA. • Whose the babies daddy? • How is “dad 1” related to mom? Look closely!
Explain why there is only one band in lane two? What does digested mean? Do you understand how to determine a childs mom and dad?
Whose blood is at the crime scene? • Whose hair is at the crime scene? • Would the DNA be the same in hair and blood? • Does the suspect’s blood match the CS blood?
What does paternity mean? • Why would a paternity test be done? • Who is the babies daddy?
EOC Question Which technique would most likely be used by forensic scientists? A. gene cloning B. gene therapy C. DNA fingerprinting D. karyotyping Which deals with the transmission of inherited traits from one generation to another? A. anatomy B. genetics C. ecology D. forensics
Biotechnology • Biotechnology - when scientists purposely change the genetic makeup of an organism (Ex: introduce a mutation) • Used in agriculture and medicine • Bacterial mutations A strain of bacteria has been developed that can digest oil to help clean oil spills Scientists are trying to produce bacteria to clean up radioactive waste
Combining DNA Fragments • Since DNA is a universal code, it can be combined from 2 or more sources • Changes the genetic composition of the living organism • This is called recombinant DNA • Can also be used to make proteins like human insulin, hepatitis B vaccine, and a clotting factor for hemophilia patients
Questions About Previous Slides 1. Define recombinant DNA - • List 4 products made by rDNA. • Define plasmid – • Where are plasmids found? • What is the purpose of “sticky ends”? • What process is used to produce human insulin?
Name 4 products produced by rDNA (recombinant DNA). • Can you identify a plasmid? • What is inserted into the bacterial plasmid?
EOC Question Which is a step in the process of producing transgenic bacteria? A. A plasmid is used to replace a faulty gene in a human cell. B. A chain of bacterial amino acids is inserted into human DNA. C. A human gene is inserted into a bacterial plasmid. D. A mutation is produced in a bacterial cell.