1. What is a Dihybrid Cross?

A dihybrid cross examines the inheritance of two different traits simultaneously. It demonstrates Mendel's principle of independent assortment, showing how genes for different traits are inherited independently of one another.

2. How Does the Calculator Work?

The calculator generates all possible combinations of parental gametes to create a 4×4 Punnett square:

Where:

• Each parent produces 4 possible gametes (for two heterozygous traits)
• The Punnett square shows all 16 possible offspring combinations
• Genotypic ratio typically follows 1:2:1:2:4:2:1:2:1 pattern
• Phenotypic ratio typically follows 9:3:3:1 pattern

3. Understanding the Results

Genotypic Ratio: Shows all possible genetic combinations and their frequencies.

Phenotypic Ratio: Shows observable traits and their frequencies based on dominant/recessive inheritance.

4. Using the Calculator

Tips: Enter genotypes using letters A/a for the first trait and B/b for the second trait (e.g., AaBb). Capital letters represent dominant alleles.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between monohybrid and dihybrid crosses?
A: Monohybrid crosses examine one trait, while dihybrid crosses examine two traits simultaneously.

Q2: Why is the phenotypic ratio 9:3:3:1?
A: This shows the 9:3:3:1 ratio of dominant/dominant, dominant/recessive, recessive/dominant, and recessive/recessive phenotypes.

Q3: What if my results don't match expected ratios?
A: Real-world results may vary due to sample size, genetic linkage, or other factors not accounted for in basic Mendelian genetics.

Q4: Can I use this for more than two traits?
A: No, this calculator is specifically for two traits. More traits would require a larger Punnett square.

Q5: How do I represent homozygous genotypes?
A: Use AA or aa for homozygous dominant/recessive for the first trait, BB or bb for the second trait.