need help with a couple of gentics monohybrid questions Watch

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hotboi01
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1) the coat colour of shorthorn cattle is controlled by a gene with two alleles. Cattle which are homozygous for the red-coat allele have red coats; those homozygous for the white coat allele have white coats. Heterozygotes have a coat in which half the hairs are red and half are white. The resulting colour is raon.

a) Devise suitable symbols for the red coat and white coat alleles.
b) draw a fully labeled geneics diagram to show the expected ratio of coat-colour phenotypes in the calves produced by mating a number of roan cows with i) a raon bull ii) a white bull

Codominance (don't understand what this means) question :
2) Draw genetics diagrams to show the ratio of phenotypes among the offspring of a pink-flowered snapdragon crossed with
a)a white-flowered snapdragon
b)a red flowered snapdragon
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fairieboi
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(Original post by hotboi01)
1) the coat colour of shorthorn cattle is controlled by a gene with two alleles. Cattle which are homozygous for the red-coat allele have red coats; those homozygous for the white coat allele have white coats. Heterozygotes have a coat in which half the hairs are red and half are white. The resulting colour is raon.

a) Devise suitable symbols for the red coat and white coat alleles.
b) draw a fully labeled geneics diagram to show the expected ratio of coat-colour phenotypes in the calves produced by mating a number of roan cows with i) a raon bull ii) a white bull

Codominance (don't understand what this means) question :
2) Draw genetics diagrams to show the ratio of phenotypes among the offspring of a pink-flowered snapdragon crossed with
a)a white-flowered snapdragon
b)a red flowered snapdragon
Codominance is when neither is recessive, and so they are both shown in the phenotype. A common example of this is ABO blood grouping, in which A and B are dominant to O, but A and B are codominant (hence the AB blood group comes about).

1a) R and W?
b) a normal punit square for i) RW x RW and ii) RW x WW (assuming you understand those already)

2)a) normal punit for RW (red and white = pink) x WW
b) same but for RW and RR

hope that helps
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