Lab Activity Blood Type Pedigree Mystery Answer Key Upd [best] Jun 2026
A pedigree is a diagram that uses standardized symbols to show the inheritance of a trait (like blood type) through multiple generations of a family.
Three babies were born on the same night in a busy municipal hospital. Unfortunately, their identification bands were misplaced. The hospital staff must use blood typing and pedigree charts of the parents to correctly assign each baby to their biological family. The Suspects (The Babies) Baby 1: Type O ( Baby 2: Type AB ( IAIBcap I to the cap A-th power cap I to the cap B-th power Baby 3: Type B (Possible genotypes: IBIBcap I to the cap B-th power cap I to the cap B-th power IBicap I to the cap B-th power i The Families (The Parents) Family Jones: Mother: Type A Father: Type AB Family Smith: Mother: Type O Father: Type O Family Brown: Mother: Type B Father: Type A Part 3: Step-by-Step Pedigree Analysis & Answer Key
To ensure students are not just guessing the answers, look for the following verification steps in their completed lab packets:
Many updated labs include the Rh factor (+/−) as an additional layer. The key explains that Rh-positive is dominant (Rh+/Rh+ or Rh+/Rh−) and Rh-negative is recessive (Rh−/Rh−). This simulates more realistic forensic genetics, where multiple markers increase certainty.
Moreover, the key often includes “common errors” notes, such as: “Mistake: assuming a Type A parent must be AA. Always consider the heterozygous possibility.” This transforms the answer key into a self-guided tutorial. lab activity blood type pedigree mystery answer key upd
allele to her offspring. Denise must have been switched at birth or has a different biological mother. Generation III (Grandchildren) Phenotype: Type O | Genotype: Deduction: Fred inherited an
Blood type is a "Multiple Allele" trait that also shows . Type A: Genotype AAcap A cap A (Dominant) Type B: Genotype BBcap B cap B (Dominant) Type AB: Genotype ABcap A cap B (Codominant — both show) Type O: Genotype (Recessive — must have two 2. The Rh Factor (+/-) Rh+ is Dominant: Genotypes ++positive positive +−positive negative Rh- is Recessive: Genotype −−negative negative (must have two negatives) 3. Earlobe Attachment Free Earlobes: Dominant ( Attached Earlobes: Recessive (
In the landscape of high school and introductory college biology education, few activities manage to blend deductive reasoning, genetic principles, and real-world medical application as seamlessly as the “Blood Type Pedigree Mystery” lab. This hands-on exercise challenges students to step into the role of genetic investigators, using the inheritance patterns of ABO blood types to solve a familial puzzle. The “answer key” for this lab, particularly in its updated form, is not merely a list of correct responses but a pedagogical tool that illuminates the core concepts of codominance, multiple alleles, and forensic genetics. Understanding the updated answer key reveals how the lab has evolved to address common student misconceptions and incorporate more rigorous analytical thinking.
Rather than a single linear path to the answer, the updated key presents branching logic. For example: “Claimant 1 has type O blood. Could they be the child of a type AB parent and a type A parent? No, because AB × A can never produce type O (which requires two i alleles).” This approach trains students in hypothesis testing. A pedigree is a diagram that uses standardized
Use this updated data table to cross-reference phenotypes and determine exact genotypes. Family / Individual Character Name Phenotype (Blood Type) Confirmed Genotype Mr. John Smith IAicap I to the cap A-th power i Mrs. Mary Smith IBicap I to the cap B-th power i The Davis Family Mr. Robert Davis IAIBcap I to the cap A-th power cap I to the cap B-th power Mrs. Susan Davis The Jones Family Mr. David Jones Mrs. Karen Jones IAicap I to the cap A-th power i The Children IAIBcap I to the cap A-th power cap I to the cap B-th power IBicap I to the cap B-th power i RRcap R cap R IBicap I to the cap B-th power i The Estate Mystery Grandfather (Deceased) IAIBcap I to the cap A-th power cap I to the cap B-th power , Genotype varies Grandmother Claimant (Grandchild?) Part 3: Step-by-Step Pedigree Analysis & Answer Key Problem 1: Matching the Mixed-Up Children
A pedigree allows us to trace a trait through generations to figure out if an individual is homozygous or heterozygous for a trait, which is crucial for identifying how recessive traits can "hide" in a family. 📝 Answers to Analysis Questions
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The ABO blood group is determined by a single gene located on chromosome 9, which has three common alleles: IAcap I to the cap A-th power : Codes for the A antigen (dominant to IBcap I to the cap B-th power : Codes for the B antigen (dominant to : Codes for no antigen (recessive to both IAcap I to the cap A-th power IBcap I to the cap B-th power The hospital staff must use blood typing and
Grades 9–12 Biology / Honors Genetics
Lab Activity: Blood Type Pedigree Mystery — Answer Key & Teacher Guide Activity Overview
Determine if a person is homozygous (AA) or heterozygous (Ai).
When working through a "Blood Type Pedigree Mystery" lab activity, students should follow a systematic logic to deduce unknown genotypes. Step 1: Identify the Definite Genotypes