probability: likelihood an event will happen and can be expressed as percentages, fractions, or decimals heredity: transmission of characteristics from parent to offspring
Probability = # of times an event is expected to occur number of chances for the event to occur EX. 225 Black mice AND 25 white mice White mice appeared 25 times Total number of mice was 250 Probability (of getting a white mouse)= 25/250 = = 0.10 OR 10% What is the probability of getting a black mouse?
Mendel Mendel’s Peas Observed 7 characteristics Observed 2 traits within each characteristic EX. CHARACTERISTIC: flower color TRAIT: purple or white Observations purple flowering plants (PFP) PFP PFP white flowering plants (WFP)
F 1 Generation Purple flowers P 1 Generation White flowers X P 1 Generation Purple flowers Self-pollination Mendel’s Experiment F 2 Generation Purple flowers (705) White flowers (224)
Chromosomes and genes Gene (located on a chromosome) codes for a characteristic (ie flower color) Different forms of a gene = allele (purple or white) Letters used to represent alleles dominant trait capitalized (purple = P) recessive lower case (white = p)
Genotypes and Phenotypes Genotype: alleles an organism inherits EX: PP Pp pp Phenotypes: appearance due to the genotype EX: PP (purple) Pp (purple) pp (white) Homozygous: both alleles are alike (PP or pp) Heterozygous: alleles are different
Rules Law of segregation: paired factors separate during meiosis (formation of gametes) Law of independent assortment: alleles sort independently of one another (not all dominant appeared together)
Homework Read p 173-175 Problems page 178 #1 Read page 179 do problems 1-3