Incomplete and Co dominance Incomplete Dominance So far

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Incomplete and Co dominance

Incomplete and Co dominance

Incomplete Dominance So far according to Mendel's rules. . .

Incomplete Dominance So far according to Mendel's rules. . .

Genes have two options (aka alleles): dominant and recessive. Dominant traits always outweigh or

Genes have two options (aka alleles): dominant and recessive. Dominant traits always outweigh or mask the recessive traits. Phenotype (outward appearance) is only dominant or recessive.

Incomplete dominance is where neither allele is dominant over the other, thus they blend

Incomplete dominance is where neither allele is dominant over the other, thus they blend their traits and produce a third phenotype RED Flower x WHITE Flower ---> PINK Flower

In snapdragons, inheritance is expressed with incomplete dominance. Homozygous dominant flowers are red (RR)

In snapdragons, inheritance is expressed with incomplete dominance. Homozygous dominant flowers are red (RR) and homozygous recessive flowers are white (WW), but the heterozygote (RW) is a blend of dominant and recessive or in this case

Incomplete Dominance

Incomplete Dominance

The trick is to recognize when you are dealing with a question involving incomplete

The trick is to recognize when you are dealing with a question involving incomplete dominance. There are two steps to this: 1) Notice that the offspring is showing a 3 rd phenotype. The parents each have one, and the offspring are different from the parents. 2) Notice that the trait in the offspring is a blend (mixing) of the parental traits.

Co = together Coexist = exist together Cocaptain = captain together Cohabitate = live

Co = together Coexist = exist together Cocaptain = captain together Cohabitate = live together Coed=educated together Coauthor=wrote together Codominance=dominant together

Codominance With codominance, a cross between organisms with two different phenotypes produces offspring with

Codominance With codominance, a cross between organisms with two different phenotypes produces offspring with a third phenotype in which both of the parental traits appear together.

I remember co dominance in the form of an example like so: red x

I remember co dominance in the form of an example like so: red x white ---> red & white spotted

In cattle the red and white shown together is called Roan

In cattle the red and white shown together is called Roan

F

F

Codominance Example in Appaloosa Horses

Codominance Example in Appaloosa Horses

Codominance example: Erminette Chickens Erminette chickens black, but not grey.

Codominance example: Erminette Chickens Erminette chickens black, but not grey.

BB = black feathers BW = black and white feathers WW = white feathers

BB = black feathers BW = black and white feathers WW = white feathers