Darwin's Theory Answers

Mary has type A blood. Her son Bill has type AB blood. Which blood type does Bill's dad have if he is homogenous for blood type?

In peas, yellow seed color (Y) is dominant to green seed color (y). A homozygous green seed pea plant is crossed with a heterozygous yellow seed pea plant. What is the predicted phenotypic ratio of the offspring based on seed color?

Pedigrees are used to help geneticists understand how traits are inherited between generations. The Romanovs, a Russian royal family, had a history of hemophilia, a sex-linked disorder that is determined by a recessive allele on the X chromosome.What is the best evidence to prove that Irene was heterozygous for hemophilia?

In a dihybrid cross for round and yellow seeds (RrYy x RrYy), what is the probability of having green and wrinkled seeds?Key: R = round r = wrinkled Y = yellow y = green

Breeders can use a Punnett square to predict the outcome of a genetic cross. If the genotype of both parents was Aa, what would be expected of the genotypes among their possible offspring?

In peas, yellow seed color (Y) is dominant to green seed color (y). Which describes an organism that has nonidentical alleles for seed color?

Glaucoma is a leading cause of blindness. Studies have linked a common form of glaucoma to three genes and more than 20 genetic loci. Which best describes glaucoma?

Which allele combination represents a male who has an X-linked recessive disorder?

Which is an external environmental factor that affects heredity?

Which of the following could be a result of selective breeding?

Gregor Mendel used pea plants that were heterozygous for each of two traits—seed color and seed shape—to generate a dihybrid cross. The phenotypic ratio of the resulting offspring was nine with round and yellow seeds, three with round and green seeds, three with wrinkled and yellow seeds, and one with wrinkled and green seeds. From these results, what could Mendel conclude?

A purebred plant that has yellow flowers is crossed with a purebred plant that has white flowers. All the offspring have yellow flowers. Which conclusion about yellow flowers is supported by these results?

Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. What is the probability of having offspring that have wrinkled seeds and yellow seed color for the cross RRYY ´ RrYy?

Which type of scientific statement is defined as a hypothesis or group of hypotheses that can be accepted as true based on repeated experimentation with similar results?

Which was most likely an effect on society that resulted from improvements in blood handling during World War I and World War II?

If a person has type B blood, which statement describes the antibodies present in his or her blood?

Frank and Maria both have normal vision. After they married, they had two daughters and a son. Both daughters have normal vision and never had children. Marco, the son, is color blind. He married Lauren, who has normal vision. Marco and Lauren had two children, Caleb and Molly. Caleb is not color blind, but Molly is. Color blindness is a sex-linked recessive trait (carried on the X chromosome). The diagram below shows the family tree, but is not shaded to show the passage of this trait. Which statement about this family’s pedigree is correct?

A student is given a list of traits and is asked to organize them in a Venn diagram as shown below. Which traits should the student put in section I (Inherited)?