12/11/14 Discussion Questions 1.Please complete this Punnett Square: Gg x Gg G = green g = yellow 2. Give the genotypic and phenotypic percentages and ratios of the offspring. and ratios of the offspring.

12/12/13 Genotypic Percentages GG= 25% Gg = 50% gg = 25% Genetypic Ratio 1:2:1 Phenotypic Percentages Green = 75% Yellow = 25% Phenotypic Ratio 3:1

Reminders Rough Draft of your Abstract is PAST DUE Science Fair is on Wed 12/10/14. Everything will be due in class on Monday 12/8/14. - Board, Journals, Demo Items, Extra copies of abstract 5 pts. EC for turning your project in anytime before The entire project! Go to our class website and register your science fair project by SAT. You MUSTdo this to have a space reserved for your project. Root quiz Exam (chapters 10 & 11) Go to room 1135 Tues or Thurs for Science Peer Tutoring during PLC

Today’s Objective: Objective: Identify and describe the stages and purpose of Meiosis as related to Genetics and Heredity. Review Mendel’s discoveries and simple Mendelian Genetics with monohybrid punnett squares and dihybrid punnett squares. Understand and explain NonMendelian inheritance patterns such as codominance and incomplete dominance

Exceptions to Mendel’s Discoveries

Trait – several possible forms of a character Gene – factor that determines traits Allele – form of a gene Hybrid – offspring of parents with different traits

Multiple Alleles When there are 3 or more forms of an allele for a geneWhen there are 3 or more forms of an allele for a gene No individual has more than two alleles, but there are more than two possible alleles in a population, so a trait will be expressed in more than two forms. Example: Blood Types Blood type gene consists of 3 alleles: A, B, O AA  Type A BO  Type B BB  Type B AO  Type A OO  Type O AB  Type AB OO  Type O AB  Type AB

Codominance Both alleles are dominant and both will be expressedBoth alleles are dominant and both will be expressed Example: Blood Type The A allele is not dominant over the B allele or vice versa.The A allele is not dominant over the B allele or vice versa. When both are present, both are equally expressed  AB blood typeWhen both are present, both are equally expressed  AB blood type

Codominance Andalusian chickens also show this pattern of inheritance. If you cross a black (BB) chicken With a white (WW) chicken You get black+white speckled (BW) chicken

Incomplete Dominance In incomplete dominance, neither allele is __________ so there is a blending of ______ when two different alleles for the same trait occur together. blendColors blend together (______________ individuals = 3 rd phenotype) dominant traits heterozygous redwhitepink RR rr Rr

Incomplete Dominance In another flower, if red ____ and blue ____ flowers are crossed, they produce a 3 rd purple ____ flower What would be the genotype ratio and phenotype ratio if you crossed two purple flowers? RR rr Rr

Incomplete Dominance Cross of two purple flowers ____ X ____ What are gamete possibilities? genotype ratio 1 RR : 2Rr : 1rr phenotype ratio red : 2 purple : 1 blue Can you have a heterozygous red or hybrid blue flower? ___ B R Rr rr Rr RR Rr redpurple blue Rr Rr no

Polygenic Traits When a single trait is controlled by several genes.When a single trait is controlled by several genes. Show a wide range of phenotypes The phenotype is produced by the interaction of more than pair of genes. Example: Human skin colorExample: Human skin color Hair color eye color

Science Fair Clean up Those moving on need to keep their projects…. You can store them in my stock room until this afternoon Those not moving on can take their projects home….you can store them in my stock room until this afternoon or you can dispose of your project. There will be a dolly for you to put your project on. Do NOT leave any of your stuff on the tables. When we return, we will start the NonMendelian Inheritance ppt

Exit Ticket 1. Please describe the purpose of meiosis. 2. What are homologous chromosomes? 3. Please describe Mendel’s research