Double the Traits, Double the Prediction!
What Is a Dihybrid Cross?
A dihybrid cross predicts the inheritance of __ traits at the same time.
Each ______ has _ alleles for ____ ______, so their __________ has _ letters (e.g., RrYy).
Traits Example:
R = round, r = wrinkled (pea shape)
Y = yellow, y = green (pea color)
FOIL Method to Find Gametes
How to get combinations of alleles from each parent (RrYy):
F = ______ RY
O = __________ Ry
I = __________ rY
L = ________ ry
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Each gamete has 1 allele for each trait (1 for shape + 1 for color)
Round and Yellow: ___
Round and Green: ___
Wrinkled and Yellow: ___
Wrinkled and Green: ___
Your Turn!
Parent Genotype: AaBB
Gametes: ______, ______
Parent Genotype: ddGg
Gametes: ______, ______
Parent Genotype: MMnn
Gametes: ______
Parent Genotype: SsTT
Gametes: ______, ______
______________Cross – A Punnett square for two traits
_________– A physical characteristic
___________– The allele combination (e.g., RrYy)
___________– The physical outcome (e.g., round yellow)
_____________– Allele that shows up if present
______________– Hidden unless both alleles are recessive
____________– A sex cell (egg or sperm)
___________– A method to find gamete combinations from 4-letter genotypes