1. What is a Punnett Square?

The Punnett square is a diagram that is used to predict the genotype and phenotype combinations of offspring from parental alleles. For blood types, it helps determine the probability of inheriting specific blood types based on parental genotypes.

2. How Does the Calculator Work?

The calculator uses the Punnett square probability formula:

Where:

• \( P \) — Probability (dimensionless)
• \( F \) — Favorable outcomes (dimensionless)
• \( T \) — Total possible outcomes (dimensionless)

Explanation: The calculator considers all possible allele combinations from both parents and calculates the probability of each blood type appearing in their offspring.

3. Blood Type Inheritance

Details: Blood type is determined by three alleles: A, B, and O. A and B are codominant, while O is recessive. The possible genotypes are AA, AO, BB, BO, AB, and OO.

4. Using the Calculator

Tips: Select the genotype (not phenotype) for each parent. Remember that AO and BO genotypes will show as blood types A and B respectively, but can pass on O to their children.

5. Frequently Asked Questions (FAQ)

Q1: Why can't I select blood type directly?
A: We need the genotype (e.g., AO) rather than phenotype (A) because two parents with blood type A (AO genotype) can have a child with blood type O.

Q2: What's the rarest blood type?
A: AB negative is the rarest (about 1% of population), while O positive is most common (about 37%).

Q3: Can two O parents have an AB child?
A: No, two O parents (OO genotype) can only have O children. AB would require one parent to have A and the other B.

Q4: How accurate is this calculator?
A: It shows theoretical probabilities based on Mendelian inheritance. Actual results may vary due to genetic factors not accounted for.

Q5: What about Rh factor?
A: This calculator focuses on ABO blood types. Rh factor follows similar inheritance patterns but wasn't included for simplicity.