In pea plants, tall stems (T) are dominant to short stems (t). Two plants of genotype Tt are crossed. What genotype ratio is expected among their offspring?

In guinea pigs, black coat (B) is dominant to white coat (b). A black guinea pig of genotype Bb is crossed with a white guinea pig. What genotype ratio is expected among the offspring?

In corn, purple kernels (P) are dominant to yellow kernels (p). A plant of genotype PP is crossed with a plant of genotype Pp. What genotype ratio is expected in the offspring?

In cattle, polled (hornless, P) is dominant to horned (p). A bull of genotype PP is mated with a cow of genotype pp. Which statement describes the genotypes of their calves?

In tomatoes, red fruit (R) is dominant to yellow fruit (r). Two plants of genotype Rr are crossed and the square is completed. How many of the four cells hold a homozygous genotype?

In chickens, feathered legs (F) are dominant to clean legs (f). Two birds of genotype Ff are mated. Which two genotypes belong in the cells marked with a question mark?

In horses, a black coat (B) is dominant to a chestnut coat (b). A mare of genotype Bb is bred to a stallion of genotype BB. Which genotype cannot appear among their foals?

In sheep, white wool (W) is dominant to black wool (w). Two black sheep are bred together. What genotypes appear among their lambs?

In one breed of dog, a dark coat (D) is dominant to a light coat (d). Two dogs of genotype Dd are bred. Which genotype fills more cells of the completed square than any other?

In fruit flies, a gray body (E) is dominant to an ebony body (e). A gray fly of genotype Ee is crossed with an ebony fly. Which genotype belongs in the cell marked with a question mark?

In pea plants, purple flowers (P) are dominant to white flowers (p). A plant of genotype Pp is crossed with a white-flowered plant. What percentage of the offspring are expected to have white flowers?

In guinea pigs, black coat (B) is dominant to white coat (b). Two guinea pigs of genotype Bb are bred together. What phenotype ratio is expected in the litter?

In rabbits, black fur (B) is dominant to white fur (b). A rabbit of genotype BB is crossed with a rabbit of genotype bb. What percentage of the young are expected to have black fur?

In fruit flies, normal wings (N) are dominant to vestigial wings (n). Two flies of genotype Nn are crossed. What percentage of the offspring are expected to have vestigial wings?

In cats, short hair (S) is dominant to long hair (s). A short-haired cat of genotype Ss is mated with a long-haired cat. What phenotype ratio is expected among the kittens?

In sheep, white wool (W) is dominant to black wool (w). Two sheep of genotype Ww are bred. What percentage of the lambs are expected to have white wool?

In chickens, feathered legs (F) are dominant to clean legs (f). A hen of genotype Ff is mated with a clean-legged rooster, and 40 chicks hatch. About how many of the chicks are expected to have feathered legs?

In horses, a black coat (B) is dominant to a chestnut coat (b). A mare of genotype Bb and a stallion of genotype Bb produce 8 foals over several seasons. About how many of the foals are expected to be chestnut?

In pea plants, round seeds (R) are dominant to wrinkled seeds (r). A plant of genotype RR is crossed with a plant of genotype Rr. What percentage of the seeds are expected to be wrinkled?

A true-breeding tall pea plant (TT) is crossed with a true-breeding short plant (tt). The F1 plants are then crossed with one another. What phenotype ratio is expected in the F2 generation?

In mice, a black coat (B) is dominant to a brown coat (b). Two mice of genotype Bb are crossed. What is the probability that any one pup has the genotype bb?

In one breed of dog, a dark coat (D) is dominant to a light coat (d). A dog of genotype Dd is bred with a light-coated dog. What is the probability that a single puppy has a light coat?

In pea plants, purple flowers (P) are dominant to white flowers (p). Two plants of genotype Pp are crossed. What is the probability that a single offspring has purple flowers?

In cattle, polled (hornless, P) is dominant to horned (p). A cow of genotype Pp is mated with a bull of genotype PP. What is the probability that a single calf is horned?

In fruit flies, a gray body (E) is dominant to an ebony body (e). Two flies of genotype Ee are crossed. What is the probability that a single offspring has the genotype Ee?

In cats, short hair (S) is dominant to long hair (s). Two cats of genotype Ss are mated, and their first kitten has long hair. What is the probability that the next kitten has long hair?

In pea plants, purple flowers (P) are dominant to white flowers (p). A plant of genotype Pp is crossed with a plant of genotype pp. Of the offspring that have purple flowers, what fraction are expected to be Pp?

In guinea pigs, black coat (B) is dominant to white coat (b). Two black guinea pigs are bred together and one pup in the litter is white. What are the genotypes of the two parents?

In cattle, polled (hornless, P) is dominant to horned (p). A polled cow is mated with a horned bull, and about half of their calves over the years are horned. What is the cow's genotype?

In corn, purple kernels (P) are dominant to yellow kernels (p). A purple-kernel plant is crossed with a yellow-kernel plant, and all 200 offspring have purple kernels. What is the purple parent's most likely genotype?

In chickens, feathered legs (F) are dominant to clean legs (f). A feathered-leg hen mated with a clean-leg rooster has 6 feathered and 6 clean chicks. If she is mated with an Ff rooster instead, what fraction of chicks are expected to have clean legs?

In rabbits, black fur (B) is dominant to white fur (b). One black rabbit, mated with white rabbits several times, produces some black young and some white young. What must be true of that black rabbit's gametes?

In cats, short hair (S) is dominant to long hair (s). Two short-haired cats have a litter that includes a long-haired kitten. Among their short-haired kittens, what fraction are expected to carry the s allele?

In pea plants, tall stems (T) are dominant to short stems (t). Two tall plants are crossed and all 30 of their offspring are tall. Which statement about the parents is best supported by this result?

In guinea pigs, black coat (B) is dominant to white coat (b). A breeder owns a black guinea pig and needs to know whether it carries the white allele. Which mating would show this most clearly in a single generation?

In tomatoes, red fruit (R) is dominant to yellow fruit (r). Which cross would produce offspring in a 1 : 2 : 1 genotype ratio?

In cattle, polled (hornless, P) is dominant to horned (p). A rancher owns a horned cow and wants to be certain that her calf is not horned. Which bull should she use?

In pea plants, purple flowers (P) are dominant to white flowers (p). Which cross would give offspring of which about half have white flowers?

In mice, a black coat (B) is dominant to a brown coat (b). A researcher wants to find out whether a black mouse carries the brown allele. Which mate would make the test useless, because every pup would be black whatever the tested mouse's genotype is?

In one breed of dog, a dark coat (D) is dominant to a light coat (d). A student wants a cross whose F1 offspring are all alike and all carry both alleles. Which cross should be used?