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Target: I will understand what probability is and how it helps explain the results of genetic crosses, and what genotype and phenotype mean. Probability - a number that describes how likely it is that a certain event will occur. Ch 5, Sec 2 Probability & heredity.
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Target: I will understand what probability is and how it helps explain the results of genetic crosses, and what genotype and phenotype mean. Probability - a number that describes how likely it is that a certain event will occur Ch 5, Sec 2 Probability & heredity
How probability relates to genetics - Mendel crossed 2 hybrid tall plants (Tt) together. What is the probability of the outcomes? Probability: - ¼ (25%) Chance TT (purebred tall) - ½ (50%) Chance Tt (hybred tall) - ¼ (25%) Chance tt (purebred short) T t TT Tt T t Tt tt
PunnetSquare - chart that shows possible combinations of alleles that can result from a genetic cross - used to calculate the probability that offspring with a certain combination of alleles will result - created by Reginald Punnett in early 1900’s *In a genetic cross, the allele that each parent will pass on to its offspring is based on probability
Phenotype - physical appearance, or visible traits Genotype - genetic makeup, or allele combinations - ex: TT, Tt, or tt Homozygous (Purebred) - organism with two IDENTICAL alleles (TT, tt) Heterozygous (Hybrid) - organism with two DIFFERENT alleles (Tt) Codominance - alleles are neither dominant nor recessive - both alleles are expressed in the offspring - ex: black chicken crossed with white chicken, offspring has both black and white feathers