The gene d controls wing shape in flies and has two alleles: d is wild-type and dominant, and d is recessive and causes flies to have downward pointed wings. the gene e controls eye development and also has two alleles: e is wild-type and dominant, and e is recessive and causes the flies to have small eyes. the two genes are located on the same chromosome. a pure-breeding fly with normal wings and small eyes was crossed with a pure-breeding fly with downward wings and normal eyes. all of the f1 progeny had a wild-type phenotype. the recombination frequency between the two genes is 14%. if an f1 individual was test crossed, what percentage of the progeny would you expect to have the wt phenotype? 43%7%28%14%86%

7 % progeny will show wild type phenotype

Explanation:

Parent 1: Normal wings and small eyes : DDee

Parent 2 : Downward wings and normal eyes : ddEE

DDee X ddEE = DdEe ( All have normal wings and normal eyes )

When a F1 individual is test crossed:

DdEe X ddee =

De/de = Parental

dE/de = Parental

DE/de = Recombinant

de/de =  Recombinant

Recombination frequency between the two genes is 14% hence DE/de and de/de will each have 7% frequency. Since DE/de ( DdEe ) will give wild type phenotype, it means that 7% progeny will have wild type phenotype.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).