Incomplete Dominance Notes #25 I can: Predict that offspring of two parents when there is no true dominant and recessive trait

Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes.

Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes.

Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes.

Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes. complete dominance incomplete dominance co-dominance multiple alleles sex-linked

R = red W = white RR RW WW red pink white Red + White = pINC INComplete dominance! Incomplete dominance is a pattern of inheritance in which neither allele is completely dominant over the other. The heterozygous phenotype is somewhere in between the two homozygous phenotypes. we CAN use two different letters to represent the different alleles In incomplete dominance, there are always 3 phenotypes. One is in the middle of the other two. R = red W = white RR RW WW genotype: red pink white phenotype:

? BB black B = black W = white Coat color in mice exhibits incomplete dominance. ? BB black

? WW white B = black W = white Coat color in mice exhibits incomplete dominance. ? WW white

? BW gray B = black W = white Coat color in mice exhibits incomplete dominance. ? BW gray

R = red W = white Flowers exhibit incomplete dominance for petal color. ? RR red

R = red W = white Flowers exhibit incomplete dominance for petal color. ? WW white

R = red W = white Flowers exhibit incomplete dominance for petal color. ? RW pink

T = tall S = short Human height follows a pattern of incomplete dominance. ? TT tall

? SS short T = tall S = short Human height follows a pattern of incomplete dominance. ? SS short

? medium height TS T = tall S = short Human height follows a pattern of incomplete dominance. ? medium height TS

Scale color in fish is controlled by two incompletely dominant alleles Scale color in fish is controlled by two incompletely dominant alleles. The homozygotes are blue and yellow. What are the genotypes for blue, yellow, and green fish? blue – yellow – green –

Wing color in birds is controlled by two incompletely dominant alleles Wing color in birds is controlled by two incompletely dominant alleles. The homozygotes are blue and red. What are the genotypes for blue, red, and purple birds? blue – red – purple –

Tooth number in Zorgs is controlled by two incompletely dominant alleles. The homozygotes have 2 and 4 teeth. What are all possible genotypes of Zorgs? 2 teeth – 4 teeth – ?? teeth –

Solving an Incomplete Dominance Problem Coat color in mice is incompletely dominant. Yellow and white-colored mice are homozygous, while cream-colored mice are heterozygous. If two cream-colored mice mate, what phenotypic ratio can we expect of their offspring? Y = yellow; W = white Solving an Incomplete Dominance Problem Y W 1. Read the problem. Underline the known alleles. Identify the type of inheritance as incomplete dominance. Y W Y Y Y 2. Choose a letter to represent each allele in the problem. 3. Circle and/or write down the genotypes of the parents. Y W W W W 4. Set up and solve Punnett Square. 5. Highlight and answer what the question is asking. parents: YW x YW yellow = 1/4 = 25% white= 1/4 = 25% cream = 2/4 = 50%

What type of inheritance? (Complete or Incomplete Dominance) Tall pea plants are crossed with short pea plants. All the offspring are tall. How do you know what type of inheritance it is?

What type of inheritance? (Complete or Incomplete Dominance) Having 10 fingers is dominant to having 12 fingers. A woman with 12 fingers has a child with a normal man and all their children have 10 fingers. How do you know what type of inheritance it is?

What type of inheritance? (Complete or Incomplete Dominance) A blue butterfly mates with a yellow butterfly. All their children are green. How do you know what type of inheritance it is?

What type of inheritance? (Complete or Incomplete Dominance) You have a black horse and a white horse on your farm. They have babies, and they’re all gray. How do you know what type of inheritance it is?

What type of inheritance? (Complete or Incomplete Dominance) You have a black horse and a white horse on your farm. They have babies, and they’re all black. How do you know what type of inheritance it is?