The coat colour of some dogs is an example of an epistatic interaction. The common alleles are black (B) and brown (b). There is a separate gene on a separate chromosome that influences coat colour; it prevents colour formation and causes a white coat. L = prevents color formation and causes a white coat l = allows colour formation to occur. If a white dog heterozygous for both traits is crossed with a black dog that is heterozygous for the color gene,  which of the following represents the phenotypes of the offspring? Select one: a. Phenotypes White Black Brown       b. Phenotypes White Black Brown       c. Phenotypes White Black Brown       d. Phenotypes White Black Brown

In cats, the locus for orange coat color is sex linked. Male cats that are black have the o+ allele, whereas those that are orange have the o allele. Females can be homozygous for the orange allele or homozygous for the black allele and will express each color, respectively. Heterozygous females are tortoise-shelled or calico, having orange and black patches. A calico cat, in addition to being heterozygous at the orange locus, also is either heterozygous or homozygous for the incompletely dominant, autosomal spotting allele (SS = large spots, Ss = small spots, ss = no spots). Manx tails are caused by a dominant trait that is lethal when homozygous. Long tails are the result of a homozygous recessive genotype. An orange male with small white spots and a manx tail is crossed to a calico female with small white spots and a manx tail. What is the probability of observing a solid black female with no spots and long tail? (Hint: All calico cats are female!)

The cross AaBb x AAbb results in which of the following phenotypic ratios? 1:2:1 1:1:1:1 9:3:3:1 1:1

Feather colour in parakeets is controlled by two genes. Blue colour (B) is dominant over absence of colour (b). Yellow colour (Y) is dominant over absence of colour (y). When a B allele and a Y allele are present, a green parakeet is produced.The probability of obtaining a female or male parakeet is the same as for humans. A green parakeet crossed with a white parakeet produced offspring with four different colour patterns.What is the genotype of the green parakeet?  Answer

Pigeons display a high color variety, here we try to understand the genetic basis of mixed red & black stippling of the feathers (kitey) and their genetic relation to black and red feather color. We conducted the following crosses: Cross Offspring kitey x kitey 16 kitey 5 black 3 red kitey x black 6 kitey 7 black red x kitey 18 red 9 kitey 6 black   Have a look at the cross results and develop a hypothesis to explain the inheritance of kitey, black and red feather color in pigeons (Hint: assume that 2 loci are involved and some type of epistasis occurs) QUESTION: 1. provide hypothesis                     2.  provide the hypothetical genotypes for each crossing

In rabbits, black hair is due to a dominant allele B and brown hair to its recessive allele b.  Short hair (H) is dominant to long hair (h).  In a cross between a homozygous black, longhaired rabbit and a brown, homozygous shorthaired one, what would the F1 generation look like?  If you did not know the genotype of an F1 rabbit, you could determine its genotype by a test cross in which it is crossed with an animal with which phenotype AND genotype If you carried out this test cross, what phenotypes and in what ratio would you expect? What phenotypes in what ratio would be expected in the F2 generation?