Before diving into the pedigree, we must establish the rules of the game. Blood typing is governed by three alleles: A, B, and O.
Step 3: Work Backwards from OffspringIf a child has Type O blood (OO), they must have received one O allele from each parent. This means that even if a parent has Type A or Type B blood, their genotype must be heterozygous (AO or BO). This is the most common "aha!" moment in the lab activity. lab activity blood type pedigree mystery answer key upd
The Grandparents: Usually, one is Type O (OO) and the other is Type A or B, establishing the presence of the recessive allele in the first generation.The "Mystery" Child: Often, students must determine if a child could belong to a specific set of parents. If the parents are Type AB and Type O, the child can only be Type A (AO) or Type B (BO). If the lab asks why a Type O child doesn't fit, the answer is that the AB parent lacks the recessive allele.The Missing Genotypes: For Type A or B individuals with one Type O parent, the answer key will always list them as heterozygous (AO or BO). Why This Lab Matters Before diving into the pedigree, we must establish
A pedigree is a visual chart that tracks a trait through generations. In a blood type mystery lab, squares represent males and circles represent females. Lines connect parents and offspring. The goal is usually to identify the blood type or genotype of a "mystery" individual or to prove paternity/maternity within a fictional scenario. This means that even if a parent has
The Blood Type Pedigree Mystery is more than a worksheet; it’s a lesson in logic and biological probability. It demonstrates how hidden traits (recessive alleles) can skip generations only to reappear later. It also highlights the importance of codominance in human variation.