In the purple penguin,an allelic series occurs at the p locus on an autosome.All alleles affect the color of feathers: p^d = dark-purple,p^m = medium-purple,p^l = light-purple,and p^vl = very pale purple.The order of dominance is p^d > p^m > p^l > p^vl.If a p^l/p^vl female is crossed to a p^d/p^mmale,the ratio of phenotypes expected among the baby penguins would be:

Two new mutant lines of a flowering plant have been obtained; one breeds true for blue flower color and the other breeds true for red flower color (wild-type flower color is purple). Consider the following crosses.
1. blue $\times$ purple $\rightarrow \mathrm { F } _ { 1 }$ all purple $\rightarrow \mathrm { F } _ { 2 } 75 \%$ purple; $25 \%$ blue
2. red $\times$ purple $\rightarrow \mathrm { F } _ { 1 }$ all purple $\rightarrow \mathrm { F } _ { 2 } 75 \%$ purple; $25 \%$ red
3. red $\times$ blue $\rightarrow \mathrm { F } _ { 1 }$ all purple

If the purple flower color results from the mixture of red and blue pigments,and all the intermediate products in the pigment pathways are colorless,what phenotypic ratios do you expect in the F₂ of cross 3?

In a wild-type fungus,protein E (encoded by the haplosufficient gene "E")normally homodimerizes,and the E-E dimer catalyzes a biochemical reaction necessary for the production of a dark pigment.E^D represents a mutant,dominant,negative allele of gene E.What is the predicted phenotype of a fungus cell of genotype E⁺/E^D,and why?