Which of the following offspring ratios is expected from a Mendelian heterozygous cross examining one gene?

A cross between a spicy variety of Capsicum annum pepper and a sweet (nonspicy) variety produces  progeny plants that all have spicy peppers. The  are crossed, and among the  plants are 56 that produce spicy peppers and 20 that produce sweet peppers. Dr. Ara B. Dopsis, an expert on pepper plants, discovers a gene he designates Pun1 that he believes is responsible for spicy versus sweet flavor of peppers. Dr. Dopsis proposes that a dominant allele P produces spicy peppers and that a recessive mutant allele p results in sweet peppers.

Are the data on the parental cross and the F₁ and F₂ consistent with the proposal made by Dr. Dopsis? Explain why or why not, using P and p to indicate probable genotypes of pepper plants.

A pure-breeding fruit fly with the recessive mutation cut wing, caused by the homozygous cc genotype, is crossed to a pure-breeding fly with normal wings, genotype CC. Their  progeny all have normal wings. F₁ flies are crossed, and the F₂ progeny have a 3:1 ratio of normal wing to cut wing. One male F₂ fly with normal wings is selected at random and mated to an F₂ female with normal wings. Using all possible genotypes of the F₂ flies selected for this cross, list all possible crosses between the two flies involved in this mating, and determine the probability of each possible outcome.

A black and white rabbit were mated. All F₁ offspring were black, and the F₂ offspring is made up of approximately ¾ black and ¼ white rabbits. 

• Draw out two Punnet squares detailing both matings.
• Supposed two white F₂ offspring were mated. What would be the phenotype and genotype of the F₃ offspring? 

Green scales (G) in a particular species of fish is dominant over blue scales (g). The following crosses are carried out, producing the progeny shown. Write out all possible genotypes of the parents in each cross. 

Human albinism is a simple recessive trait. Determine the genotypes of the parents for each offspring combination 

i. A wild-type male and albino female have 6 wild-type children 

Human albinism is a simple recessive trait. Determine the genotypes of the parents for each offspring combination

ii. A wild-type male and albino female have 8 children, 4 wild-type, and four albino 

Compare and contrast the following terms:

monohybrid cross and test cross

For the cross BB×Bb, what is the expected genotype ratio? What is the expected phenotype ratio?