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🧬 Dihybrid Cross Punnett Square (4×4)

Trait 1 uses A/a and Trait 2 uses B/b. Capital letter = dominant; lowercase = recessive.

👩‍🧬 Mother’s traits

Trait 1 (A/a)

Trait 2 (B/b)

👨‍🧬 Father’s traits

Trait 1 (A/a)

Trait 2 (B/b)

Inputs update results instantly (AJAX-style). No page reload.

📊 Key outcomes

Phenotypic ratio (A_B_ : A_bb : aaB_ : aabb)—

Genotypic ratio (9 classes)—

Classic AaBb × AaBb→ 9:3:3:1

🧩 Punnett Square (4×4)

♂︎\♀︎

—

Headers show parental gametes (AB, Ab, aB, ab); inner cells show offspring genotypes (e.g., AaBb).

🧾 Resulting probabilities (%)

AABB	AABb	AAbb	AaBB	AaBb	Aabb	aaBB	aaBb	aabb
—	—	—	—	—	—	—	—	—

Genotypic ratio (AABB:AABb:AAbb:AaBB:AaBb:Aabb:aaBB:aaBb:aabb): —

Phenotypic ratio (A_B_ : A_bb : aaB_ : aabb): —

🔠 Allele legend

Symbol	Meaning
A	Dominant allele of Trait 1
a	Recessive allele of Trait 1
B	Dominant allele of Trait 2
b	Recessive allele of Trait 2

🧮 Step-by-step derivation (click to expand)

📚 References

Standard Mendelian inheritance (complete dominance; Law of Independent Assortment).

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