Cross homozygous dominant tall plant and a heterozygous tall plant. a. What are the Parent genotypes? b. What are the F1 phenotype frequencies? c. What are the F1 genotype frequencies?

Cross homozygous dominant tall plant and a heterozygous tall plant. a. What are the Parent genotypes? b. What are the F1 phenotype frequencies? c. What are the F1 genotype frequencies? T T TT TT T T = tall T = short TT and Tt All Tall 2 TT : 2 Tt tall tall t Tt Tt tall tall

TtHh T = straight-tailed t = curly-tailed H = short-haired What gametes can be formed from the following organism? TtHh T = straight-tailed t = curly-tailed H = short-haired h = long-haired

TtHh Use the foil method: TH Th tH th What gametes can be formed from the following Straight-tailed, short-haired dog? TtHh Use the foil method: TH Th tH th What are the genotype and phenotype ratios from crossing TtHh with TTHH?

TtHh x TTHH TH Th tH th TH TH TH TH T = straight tailed t = curly tailed H = short haired h = long haired TH F1 Phenotype ratio: F1 Genotype ratio: TH TH

TH Th tH th TH TTHH TTHh TtHH TtHh TH TTHH TTHh TtHH TtHh TH TTHH TTHh T = straight tailed t = curly tailed H = short haired h = long haired Straight, short Straight, short Straight, short Straight, short TH TTHH TTHh TtHH TtHh Straight, short Straight, short Straight, short Straight, short F1 Phenotype ratio: All straight-tailed All short-haired F1 Genotype ratio: 4 TTHH 4 TTHh 4 TtHH 4 TtHh TH TTHH TTHh TtHH TtHh Straight, short Straight, short Straight, short Straight, short TH TTHH TTHh TtHH TtHh Straight, short Straight, short Straight, short Straight, short

If cross-pollinating a red snapdragon and white snapdragon produce all pink snapdragons: a. What is the percent chance a white flower will result from the self pollination of one of the pink offspring? b. What kind of inheritance is this?

R R RW RW W R = red W = white pink pink W RW RW pink pink

R W RR RW R W RW WW R = red W = white pink W RW WW pink white 25% chance two pink-flowered plants produce a white-flowered plant Type of inheritance: incomplete dominance

IA = A allele IB = B allele i = O allele Can a type A mother and type B father have a child with type O blood? IA = A allele IB = B allele i = O allele Genotype possibilities for Type A mom: IAIA or IAi Genotype possibilities for Type B dad: IBIB or IBi

IA = A allele IB = B allele i = O allele Can a type A mother and type B father have a child with type O blood? IA = A allele IB = B allele i = O allele Ia i Genotype possibilities for Type A mom: IAIA or IAi Genotype possibilities for Type B dad: IBIB or IBi IaIb Ibi Ib Type AB Type B i Iai ii Type A Type O

What percent chance does a child have of being colorblind if the mother is normal but a carrier, and the father is normal? What if the father was colorblind? What is mom’s genotype? What is dad’s genotype?

What percent chance does a child have of being colorblind if the mother is normal but a carrier, and the father is normal? What if the father was colorblind? Problem 1: Carrier mother, Normal father What is mom’s genotype? XBXb What is dad’s genotype? XBY

Problem 1: Carrier mother, Normal father What is mom’s genotype? XBXb What percent chance does a child have of being colorblind if the mother is normal but a carrier, and the father is normal? What if the father was colorblind? Problem 1: Carrier mother, Normal father What is mom’s genotype? XBXb What is dad’s genotype? XBY Daughters: 0% Sons: 50% XB Y XBXB XBY XB Normal female Normal male Xb XBXb XbY Carrier female Colorblind male

What percent chance does a child have of being colorblind if the mother is normal but a carrier, and the father is normal? What if the father was colorblind? Problem 2: Carrier mother, Colorblind father What is mom’s genotype? XBXb What is dad’s genotype? XbY

Problem 2: Carrier mother, Colorblind father What percent chance does a child have of being colorblind if the mother is normal but a carrier, and the father is normal? What if the father was a carrier? Problem 2: Carrier mother, Colorblind father What is mom’s genotype? XBXb What is dad’s genotype? XbY Daughters: 50% Sons: 50% Xb Y XBXb XBY XB Carrier female Normal male Xb XbXb XbY Colorblind female Colorblind male

Feather length in ducks can be short or long Feather length in ducks can be short or long. Choose a letter to use for the feather length gene. Determine which allele (short or long) is dominant and which is recessive. Supply the genotypes and phenotypes of the individuals in the pedigree. You will have five individuals where you only know one allele.

Feather length in ducks can be short or long Feather length in ducks can be short or long. Choose a letter to use for the feather length gene. Determine which allele (short or long) is dominant and which is recessive. Supply the genotypes and phenotypes of the individuals in the pedigree. You will have five individuals where you only know one allele. ff ff ff ff F = short f = long ff

Feather length in ducks can be short or long Feather length in ducks can be short or long. Choose a letter to use for the feather length gene. Determine which allele (short or long) is dominant and which is recessive. Supply the genotypes and phenotypes of the individuals in the pedigree. You will have five individuals where you only know one allele. F_ F_ F_ ff F_ F_ F_ F_ ff F_ F_ F_ F_ ff ff F_ F = short f = long F_ ff F_ F_

Feather length in ducks can be short or long Feather length in ducks can be short or long. Choose a letter to use for the feather length gene. Determine which allele (short or long) is dominant and which is recessive. Supply the genotypes and phenotypes of the individuals in the pedigree. You will have five individuals where you only know one allele. Ff Ff Ff ff F_ F_ Ff Ff ff F_ Ff Ff Ff ff ff F_ F = short f = long F_ ff Ff Ff

An unaffected man marries a woman who is a carrier for Duchenne Muscular Dystrophy, which is attributed to an X-linked gene. They have four children, one with Duchenne, one carrier daughter and a daughter and son who are unaffected. The child with Duchenne Muscular Dystrophy dies in childhood. The carrier daughter marries and has three children of her own, two of which are carriers and one of which is unaffected. a. Draw a pedigree for this family. b. What is the most likely sex of these two carrier children given the fact that they are unaffected by the X-linked gene?

An unaffected man marries a woman who is a carrier for Duchenne Muscular Dystrophy, which is attributed to an X-linked gene. They have four children, one with Duchenne, one carrier daughter and a daughter and son who are unaffected. The child with Duchenne Muscular Dystrophy dies in childhood. The carrier daughter marries and has three children of her own, two of which are carriers and one of which is unaffected. a. Draw a pedigree for this family. b. What is the most likely sex of these two carrier children given the fact that they are unaffected by the X-linked gene? -For a sex-linked recessive disorder, only females can be carriers. XDY XDXd XDXd XDY XDXD XDY XdY or XDXD XDXd XDXd XDXD

Male Normal none 44 2

Male Abnormal XXY 44 3

Female Normal Trisomy 21 45 2

Male Abnormal Trisomy 18 45 2

Male Abormal Trisomy 13 45 2