Why are punnet squares a useful model for studying traits and genetic disorders? 2.Make a dihybrid cross Punnett square for the dihybrid cross YyRr and yyrr.

1. Create a Punnett square showing the genotypes of the offspring for a homozygous dominant purple plant crossed with a heterozygous purple plant. Be sure to include the genotype and phenotype ratios. 2. In a population of snapdragons, two heterozygous pink individuals mate. What is the percent chance that a PINK plant will be the offspring? Include a Punnett square to show your work. What type of dominance does this plant show? 3. There was a mix of up children in the maternity ward of a hospital. The children in question and their blood types are listed below. Child 1: type A (genotype I^I^ or I^i) Child 2: type B (genotype 181³ or 1³i) Child 3: type AB (genotype IIB) Child 4: type O (genotype ii) a. Which child or children could belong to a couple having AB and O blood types? Show your work. b. Based on the previous question, is it possible to prove paternity based on blood types? Explain. Lab Report Mendelian Genetics 201

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4. Allele specific oligo-nucleotide hybridization is a genetic test used to look for single nucleotide polymorphisms (SNPS) associated with genetic diseases. It uses short sequences of labeled DNA as probes to bind onto either the normal allele or mutated allele in a patient's sample. Given that hemocystinuria is an autosomal recessive disease, use the results from the ASOH test below to determine the GENOTYPE and PHENOTYPE of the newborns born at Henry Mayo Hospital this week. Luis Mina Emma Elias Genotype Phenotype Allele H probe Allele h probe Luis Mina Emma Elias