Question

30 POINTS 30 POINTS 30 POINTS JUST ONE QUESTION BELOW TO ANSWER

In cattle (R) is codominant to white (W) fur. Roan is the name of the color that results from codominance. What are the possible results if a white male is crossed with a roan female? Make sure to give genotypic AND phenotypic ratios in your answer.

Answer 1

Gregor Mendel knew how to keep things simple. In Mendel's work on pea plants, each gene came in just two different versions, or alleles, and these alleles had a nice, clear-cut dominance relationship (with the dominant allele fully overriding the recessive allele to determine the plant's appearance

`by \: the \: way \: your \: introduction`

Answer 2

[insert colour?] = R

white = W

roan = RW

1) figure out the genotypes of the parents.

Since this a codominance problem, in order to be one colour or the other, an individual must be homo_zygous for that trait and in order to be a roan, an individual must be hetero_zygous so these will be the parent's genotypes:

male =
`WW`

female =
`RW`

2) produce a punnet square and solve

A cross between a homo_zygous parent and a hetero_zygous parent will produce a 2 by 1 punnet square. They can only produce two kinds of offspring and in this question, the possible results are either a white cattle or a roan cattle. Their offspring's genotypes and phenotypes are as follows:

genotypic ratios:

WW : WR

[1 : 1] or [0.50 : 0.50] or [50% : 50%]

phenotypic ratios:

white : roan

[1 : 1] or [0.50 : 0.50] or [50% : 50%]