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Monohybrid Crosses . Review: Gene. Portion of DNA (nitrogen bases) that codes for a trait. Review: Allele. Two different forms of a gene: Dominant and Recessive. Punnett Square. Tool used to predict the genotypes and phenotypes of offspring. What is Monohybrid Cross?.
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Review: Gene Portion of DNA (nitrogen bases) that codes for a trait
Review: Allele Two different forms of a gene: Dominant and Recessive
Punnett Square Tool used to predict the genotypes and phenotypes of offspring
What is Monohybrid Cross? Punnett square using only one trait.
If purple is dominant and white is recessive, cross a purebred (homozygous dominant) purple flower with a white flower. Monohybrid Cross and Mendel Which allele is dominant? Purple X PP pp
PP x pp p p Pp Pp P P Pp Pp
Pp x Pp 1st generation Self Pollinates P p PP P Pp p Pp pp
Example #1 A male that is heterozygous for purple hair is crossed with a orange haired woman. What chance to they have in producing a purple haired child? Orange haired child?
Example #2 If a man that is a purebred with big ears marries a heterozygous woman for this trait, what is the chance that their first child might express the dominant trait? Big ears = B and Little ears = b
Example #3 A couple is heterozygous for the gene for big nose. They are about to have a child and hope that it has a small nose. Do they have a chance? How much of a chance? B = Big nose and b = small nose
What is a Dihybrid Cross? Punnett square using only two traits, with two alleles for each trait.
Dihybrid Cross Phenotypic Ratio =
What is the Law of Independent Assortment? Genes/Alleles for different traits separate independently during the formation of gametes.
A man with hairy ears and is heterozygous for a unibrow marries a woman that is a carrier for both traits. What is the chance that their children will be normal? (Non-hairy ears = H, Hairy ears = h, Unibrow = B, Two eyebrows = b)
If a blue-eyed female is married to a heterozygous brown-eyed male and the female is left-handed as is the male, with brown eyes being dominant over blue eyes and right-handedness dominate over left handedness, what will the offspring of this couple look like?