GENE Expression Selective breeding, hybridization, polygenic traits & epistasis SELECTIVE BREEDING The crossing of desired traits from plants or animals Produces offspring with both characteristics Selective breeding is responsible for the wide variety of dog breeds that exist in the world today, and has influenced dog shapes and sizes for thousands of years. https://www.youtube.com/ watch?v=CDnsj25h0Ek HYBRIDIZATION This Technique attempts to blend desirable but different traits INTERBREEDING: (crossing 2 genetically different species) Polygenic Traits traits that are affected by more than one gene EX: skin colour, height, weight Many different genes located on different chromosomes POLYGENIC TRAITS ARE CONTINUOUS There are Multiple genes and each gene can have Multiple alleles This means there is a WIDE range of possible phenotypes The more genes or alleles that contribute to the trait, the larger the possible variation can be. EPISTASIS Sometimes two gene pairs cooperate to produce a phenotype that neither can produce alone. Can mask the expression of other genes Pleiotropic Gene All genes interact with the environment. At times it is difficult to identify how much of the phenotype is determined by the genes (nature) and how much is determined by the environment (nurture). Can you think of a trait that might be affected by the environment? And how? https://www.youtube.com/watch?v=YJH GfbW55l0 WHAT IS MORE IMPORTANT IN DEVELOPMENT ? Genetics or Environment ? Nature refers to all of the genes and hereditary factors that influence who we are from our physical appearance to our personality characteristics Nurture refers to all the environmental variables that impact who we are, including our early childhood experiences, how we were raised, our social relationships, and our surrounding culture. DEBATE (DECEMBER 17 th ) Research the issue Reflect on your findings Discuss the various viewpoints with others Prepare for the class debate Foods derived from organisms whose genetic material (DNA) has been modified in a way that does not occur naturally EX: apples that dont turn brown DEBATE SIGN UP 3 topics, each have a PRO and CON team 5 people max per side of each debate 4 people will state their teams arguments and last person will rebuttal 6 minutes total team argument and 2 minutes for rebuttal The class will vote on the winner!