Unit Test Answers

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?

A pea plant exhibits a recessive trait. Which statement is most likely true about the plant?

The results of Thomas Hunt Morgan’s last cross are shown in the Punnett square below. Which of Thomas Hunt Morgan's hypotheses was valid based on these results?

Which of Mendel’s generations was allowed to self-pollinate?

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?

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?

In the F2 generation of Mendel’s crosses,

Hemophilia is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree. In the pedigree that is shown, which represents Irene's allele combination?

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?

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

A scientist is studying fruit fly wings. Straight wings are dominant, and curly wings are recessive. Which statement correctly describes the F1 generation if a straight-winged parent is crossed with a curly-winged parent and if both parents are true breeding?

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

In pea plants, tall plant height is dominant over short plant height. If there are 200 short plants in the F2 generation from a cross that followed Mendel’s methods, about how many plants will be tall in that generation?

The flowchart below shows the three generations of a cross between a pea plant that has yellow pods and a pea plant that has green pods. Green pods are the dominant trait. The flowchart is missing the labels that describe the traits.In which squares should the phrase “Green pods” appear?

A scientist wants to examine a genetic disease in humans. The scientist hypothesizes that the disease can be treated by using gene therapy. Humans take a long time to reproduce and develop, so the scientist will have to

Which statement about inheritance is true?

Which is the best example of a hypothesis leading to new experimental methods?

The table below summarizes Mendel’s results for the F2 generation.Mendel’s ResultsPlant height787 tall277 shortFlower color705 purple224 whitePod color428 green152 yellowPod shape882 inflated299 constrictedSeed color6,022 yellowx greenSeed shape5,474 smooth1,850 wrinkledWhat number should replace the letter x in the “Seed color” row?

Which statement is always true when describing sex-linked inheritance?

Hemophilia is an X-linked recessive disorder (Xh) that is passed through generations and can be traced by using a pedigree. What is the probability that a female child of Charles and Marie would suffer from hemophilia?

Which symbol is used to label a male that expresses a sex-linked disorder on a pedigree?

The offspring of a particular cross are 100 percent heterozygous for the trait of plant height. What were the most likely genotypes of the parents?

Which includes the physical characteristics of an organism?

Hemophilia is an X-linked recessive disorder (Xh) that is passed through generations and can be traced by using a pedigree. Based on the pedigree that is shown, which describes John?

What is the purpose of using a pedigree?