3/10/14 th 116 Day of School Learning goal (7.L.2.1): I will be able to explain why offspring that result from sexual reproduction (fertilization and meiosis) have greater genetic variation than offspring that result from asexual reproduction (budding and mitosis). Due Today: Meiosis diagram and progress reports Evening Assignment: Finish vocabulary flashcards or chart; Study for Test On the slip of paper write your name and answer the following questions: Which type of reproduction leads to more genetic variation? Explain why. Use the pictures below as part of your explanation. Asexual reproduction Do Now Sexual reproduction Meiosis is the process by which the number of chromosomes is reduced by half to form gametes (reproductive cells: sperm & egg in humans and animals or pollen & ovule in plants). This Punnett square shows how alleles separate when sex cells form during meiosis. It also shows the possible allele combinations that can result after fertilization occurs. (READ pages C98-100 in the green Prentice Hall textbook). Meiosis and Punnett Squares Fertilization is the process that takes place when a male gamete (sperm) and a female gamete (egg) combine to form one new cell. In humans, an egg cell with 23 chromosomes joins a sperm cell with 23 chromosomes to form a new 2n cell with 46 chromosomes. (READ pages C117-119 yellow McDougal book). Why does sexual reproduction require meiosis? Fertilization As you watch and listen, write in your science notebook some sources of genetic variation (i.e. things that lead to differences in traits and individuals). http://learn.genetics.utah.edu/content/variation/sources/ Source of Genetic Variation: Mutation & Reproduction (Recombination) http://www.biotopics.co.uk/genes1/asexual_and_sexual_reproduction.html In your science notebook, READ and take NOTES on the differences between asexual vs. sexual reproduction. Think about how genes (traits) are passed from parent to offspring for each. Also note some examples of each type. Which type of reproduction leads to more genetic variation and why? Genetic Variation: Sexual vs. Asexual Reproduction McDougall pgs. C102-103 Homologous Chromosomes (from father & mother) Sister chromatids (replicated chromosomes) http://www.phschool.com/science/biology_place/labbench/lab3/homologs.html Key Terms http://www.phschool.com/science/biol ogy_place/labbench/lab3/homologs.ht ml http://kids.britannica.com/comptons/art-90111/A-homologous-pair-ofchromosomes-consists-of-one-chromosome-from Homologous Chromosomes (from father & mother) Sister chromatids (replicated chromosomes) Meiosis: process of cell division where DNA is replicated (copied) then separated and divided twice to produce new cells called gametes (reproductive cells) Key Terms Read McDougall pages C120-121 about Meiosis. Then watch the Meiosis animation detailed on the next slide. Use the two resources to create a labeled diagram showing and describing what happens to the chromosomes in each stage of meiosis. Meiosis Watch the Meiosis (Narrated) animation and take notes on what happens to the DNA (genes) and chromosomes during each stage of meiosis. Turn on show text to help you take notes. http://www.sumanasinc.com/webcontent/animations/content/meiosis.html Meiosis On the FRONT Acquired Trait On the BACK Definition/characteristics: A trait or characteristic that is developed or learned through life. Traits you aren’t born with. Traits GENERALLY not controlled by DNA. Examples: Walking, speaking English, dyed hair, pierced ears, Glasses, skin cancer? Acquired trait Inherited trait Sexual reproduction Heredity DNA Chromosome Gene Allele Meiosis & Stages Genotypes Phenotype Dominant Recessive Gregor Mendel Pea Plants Genetic Variation Fertilization Gametes Asexual Reproduction Punnett Square Monohybrid cross Homozygous (Purebred) Heterozygous (Hybrid) Mutation Genetic Disorder Sickle Cell Anemia Hemoglobin Pedigree Genetics Vocabulary chart or flashcards due 3/12/14 Choose ONE of the following projects to do as a summative MAJOR assessment for the Genetics Unit. Do detailed, quality work to get full credit. Selective Breeding vs. Genetic Modification Corn is one of the most manipulated crops. Create a Presentation or Poster comparing traditional selective breeding vs. genetic modification (GMO). Explain the two methods and then show some specific corn varieties/cultivars that were created with each method and how. Genes associated with inherited traits We learned about several common inherited human traits. Pick at least 10 traits to research and which genes control these traits. Include pictures of the traits phenotypes as part of your presentation. You may complete as a Word document or presentation. Inheritance of Eye Color Create a Powerpoint presentation about the genetics of eye color. Include information about the different types of eye color, any genes that are associated with eye color, and how eye color is inherited. In your final slide, explain how YOU inherited your eye color. Myths of Human Genetics Dr. John McDonald from the University of Delaware has written that many of the inherited traits students learn in genetics class AREN’T really inherited in a simple dominant vs. recessive pattern that is taught. Create a Powerpoint to review his arguments and compare it to what MOST genetics students learn. Meiosis Game Create a game to help students learn the steps of meiosis. Students must answer questions about chromosomes, genes, DNA, and meiosis to advance through the stages of meiosis I and meiosis II. You win when you reach the final gamete stage. Plant Genetics Grow two different species of plants and create a digital comparison of their phenotype similarities and differences (appearance, size, growth rate, etc). Then research the genetics of the two species summarizing what you find. Include the number of chromosomes and genome size Expanded Traits Survey Create YOUR OWN survey of ten inherited traits. You may use 5 of the ones we did but must include 5 new ones. Sample at least 50 people. Write up your finds as a Research Investigation Article – but with more detailed and thorough sections than we did as a class. Genetic Disorders Create a Presentation about a specific genetic disorder. You must include the following information about that disorder: description, signs/symptoms, how it’s inherited or acquired, genes affected (including the mutation if known), incidence, and treatment. GMOs in the News Farmers and scientists use GMOs to create better crops. Write a news article picking a specific GMO and discuss the process, the benefits, and risks of using that GMO History of Genetics Create a timeline about the history of genetic knowledge starting with ancient times (ex. Biblical times) through the present. You must have at least 15 descriptions along the timeline. Selective Breeding in Dogs Dog Breeders use selective breeding to improve dog breed. Create a brochure to explain the selective breeding process and use specific examples to show how breeders have gotten new dog breeds. Pedigree Analysis Create a pedigree of at least three generations using a single inherited trait. You must use a REAL family either your own or one you research. Include a Punnett square from each generation to show how that trait was inherited (3 total) Genetics Projects – due 3/21/14 This evening… 1. Finish vocabulary. 2. Test Wednesday over • • • • Traits Punnett squares Pedigrees Meiosis Evening Assignment