Biology 9700 · AS & A Level · Natural and artificial selection
Natural and artificial selection — practice question
In shorthorn cattle, coat colour is determined by a codominant pair of alleles. The coat may be red, white or roan, and roan is a red-and-white mixture. A separate pair of alleles controls whether horns are present. The allele for horns is recessive to the allele for hornless cattle.
(a(i))[2]
Select appropriate symbols for each of the following:
allele for red coat colour
allele for white coat colour
allele for horns
allele for no horns
(a(ii))[3]
Using the symbols you have chosen, give the genotypes of:
white, hornless cattle
roan, horned cattle
(b)[4]
Some fast-growing breeds of cattle have been produced by artificial selection. Outline how artificial selection differs from natural selection.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “$C^R C^w$ and $h h$.” …