Unit Test Answers

Pedigrees help geneticists understand how traits are inherited between generations. Red-green color blindness is a sex-linked disorder that is determined by a recessive allele on the X chromosome.If Brian has a son who is color-blind, what is known about the genotype of the son's mother?

If Mendel had crossed a true breeding dominant plant with a true breeding recessive plant, in which of the three generations is the recessive trait visible?

Cystic fibrosis is a genetic disorder. It is a recessive trait that is determined by two alleles. Suppose two parents each carry at least one recessive allele, but neither of them has cystic fibrosis. Which statement reflects the likelihood of a child of these parents having cystic fibrosis?

Mendel’s pea plants had either purple or white flowers. This means that the plants

Which represents the cross between parent plants if one is heterozygous and has yellow-colored pods and the other is homozygous and has green-colored pods?

Mendel was able to study seven traits in all the pea plants in each generation. Which of his hypotheses allowed him to analyze each trait separately?

Red-green color blindness is an X-linked recessive disorder. What is the probability of the offspring having red-green color blindness for the cross that is represented by the Punnett square?

The pedigree traces red-green color blindness. Which family members have red-green color blindness?

In roses, red flowers and long stems are dominant traits. A rose plant that is homozygous for both red flowers and long stems is crossed with a rose plant that is heterozygous for red flowers and homozygous for short stems. What percentage of the offspring will exhibit red, long-stemmed flowers?

The Punnett square predicts the ratio of genotypes in the offspring based on the genotypes of the parents. Which Punnett square represents a cross between a mom who is heterozygous for dimples and a dad who is homozygous for no dimples?

Hemophilia is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree. Who has hemophilia in the pedigree that is shown?

Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. Which Punnett square represents the correct way to set up the cross RRYy ´ RrYY?