Punnett square problem solving example

The Punnett square is a diagram that is used to predict an outcome of a particular cross or breeding experiment. It is named after Reginald C. Punnett, who devised the approach, and is used by biologists to determine the probability of an offspring’s having a particular genotype. The Punnett square is a tabular summary of every possible combination of one maternal allele with one paternal allele for each gene being studied in the cross. These tables give the correct probabilities for the genotype outcomes of independent crosses where the probability of inheriting copies of each parental allele is independent. The Punnett Square is a visual representation of Mendelian inheritance. Why is it important for you to know about Punnett squares? The answer is that they can be used as predictive tools when considering having children. Let us assume, for instance, that both you and your mate are carriers for a particularly unpleasant genetically inherited disease such as cystic fibrosis click this icon to hear the preceding name pronounced. Of course, you are worried about whether your children will be healthy and normal. For this example, let us define “A“ as being the dominant normal allele and “a“ as the recessive abnormal one that is responsible for cystic fibrosis. As carriers, you and your mate are both heterozygous (Aa). This disease only afflicts those who are homozygous recessive (aa). The Punnett square makes it clear that at each birth, there will be a 25% chance of you having a normal homozygous (AA) child, a 50% chance of a healthy heterozygous (Aa) carrier child like you and your mate, and a 25% chance of a homozygous recessive (aa) child who probably will eventually die from this condition. #independentCrosses #breedingExperiment #GeneticsLecture #inheriting #ReginaldCPunnett #punnettSquare #geneticallyInheritedDisease #MendelianInheritance #Genotype #PunnettSquares #biology #monohybridCross #dihybridCross #probability #Phenotype #Alleles #Homozygous #Heterozygous #DominantAllele #RecessiveAllele #NikolaysGeneticsLessons #geneticCross #monohybrid #Genetics #cross #mendelian #2MinuteClassroom #crosses #inheritence #example #simple #recessive #Dominant #Genes