Exam 11: Patterns of Inheritance

Hemophilia is a genetic disease that has plagued the royal houses of Europe since the time of Queen Victoria, who was a carrier. Her granddaughter, Alexandra, married Nicholas II, the last czar of imperial Russia. Alexandra was a carrier for hemophilia, but Nicholas was normal. Their son, Alexis, was afflicted with the disease. Based on this scenario, it is most likely that

In pea plants, tall plants are dominant over short, and green pods are dominant over yellow. If you crossed true- breeding tall, green- podded plants with true- breeding short, yellow- podded plants, and then crossed the F1 individuals among themselves, what proportion of the F2 offspring would you expect to be tall and yellow- podded?

Sickle- cell anemia is caused by a recessive mutation in the hemoglobin gene. However, heterozygote individuals also show a small percentage of sickled red blood cells. What type of inheritance pattern is this an example of?

What is the reason for the prevalence of the sickle- cell allele in African populations?

Human eye color is the result of

Which disorder is characterized by an abnormal number of autosomes?

The human genome contains 46 chromosomes. There are 22 pairs of (type of chromosome) and one pair of (type of chromosome).

When the expression of a trait is influenced by the action of many genes, the pattern of inheritance is called

The genetic makeup of an individual is the

Imagine that a newly discovered species of fish normally has three eyes (E), but the rare mutation (e) causes "diopthalmic" fish with two eyes to be born. In addition, eye color in these fish is inherited similarly to humans, with black eyes (B) being dominant to blue (b). Assuming these two genes are carried on separate chromosomes, what must the genotypes of two black- eyed, three- eyed parents be if they have a blue- eyed, diopthalmic son?

The blood types of humans are an example of .

In human blood types, the alleles for A and B are said to be _ present in an individual.

When Mendel used true- breeding white flowers and true- breeding purple flowers as the parental generation, what were the results? (Purple flower is dominant over white.)

Autosomal nondisjunction can result in

Which disorder is more common among the babies of older mothers?

Hemophilia is a sex- linked recessive gene that causes a blood disorder. What are the chances that the daughter of a normal man and a heterozygous woman will have hemophilia?

When alleles on a pair of homologous chromosomes move into different gametes during meiosis, this demonstrates

Peas were a good organism of choice for Mendel because

Albinism results from a recessive allele. Which of the following describes the expected offspring from a normally pigmented male (who had an albino father) and an albino wife?

Human skin color is the result of