Exam 14: Mendel and the Gene Idea

Use the following information to answer the questions below. Skin colour in a certain species of fish is inherited via a single gene with four different alleles. -How many different types of gametes would be possible in this system?

The frequency of heterozygosity for the sickle-cell anemia allele is unusually high, presumably because this reduces the frequency of malaria. Such a relationship is related to which of the following?

The fact that all seven of the pea plant traits studied by Mendel obeyed the principle of independent assortment most probably indicates which of the following?

Given the parents AABBCc × AabbCc, assume simple dominance for each trait and independent assortment. What proportion of the progeny will be expected to phenotypically resemble the first parent?

Mendel's second law of independent assortment has its basis in which of the following events of meiosis I?

Use the following information to answer the questions below. A woman who has blood type A positive has a daughter who is type O positive and a son who is type B negative. Rh positive is a trait that shows simple dominance over Rh negative and is designated by the alleles R and r, respectively. A third gene for the MN blood group has codominant alleles M and N. -If both children are of blood type M, which of the following is possible?

Why did the F₁ offspring of Mendel's classic pea cross always look like one of the two parental varieties?

An obstetrician knows that one of her patients is a pregnant woman whose fetus is at risk for a serious disorder that is detectable biochemically in fetal cells. The obstetrician would most reasonably offer which of the following procedures to her patient?

Use the following information to answer the questions below. Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a ?white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. -The flower colour trait in radishes is an example of which of the following?

Two plants are crossed, resulting in offspring with a 3:1 ratio for a particular trait. What does this suggest?

The individual with genotype AaBbCCDdEE can make many kinds of gametes. Which of the following is the major reason?

The following questions refer to the pedigree chart in the figure below for a family, some of whose members exhibit the dominant trait, W. Affected individuals are indicated by a dark square or circle. -What is the genotype of individual II-5?

When both traits are exhibited in the phenotype, it is said that the alleles display

Use the following information to answer the questions below. A certain (hypothetical) organism is diploid, has either blue or orange wings as the consequence of one of its genes on chromosome 12, and has either long or short antennae as the result of a second gene on chromosome 19, as shown in this figure. -A female with a paternal set of one orange and one long gene chromosome and a maternal set comprised of one blue and one short gene chromosome is expected to produce which of the following types of eggs after meiosis?

Use the following pedigree shown below for a family in which dark-shaded symbols represent individuals with one of the two major types of colon cancer. Numbers under the symbols are the individual's age at the time of diagnosis. -From this pedigree, how does this trait seem to be inherited?

Use the following pedigree shown below for a family in which dark-shaded symbols represent individuals with one of the two major types of colon cancer. Numbers under the symbols are the individual's age at the time of diagnosis. -What is the genotype of the deceased individual in generation II?

Hydrangea plants of the same genotype are planted in a large flower garden. Some of the plants produce blue flowers and others pink flowers. This can be best explained by which of the following?

Mendel was able to draw his ideas of segregation and independent assortment because of the influence of which of the following?

Use the information given here to answer the following questions. Feather colour in budgies is determined by two different genes, Y and B, one for pigment on the outside and one for the inside of the feather. YYBB, YyBB, or YYBb is green; yyBB or yyBb is blue; YYbb or Yybb is yellow; and yybb is white. -Two blue budgies were crossed. Over the years, they produced 22 offspring, 5 of which were white. What are the most likely genotypes for the two blue budgies?

Refer to the following information to answer the questions below. Gene S controls the sharpness of spines in a type of cactus. Cacti with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cacti have dull spines. At the same time, a second gene, N, determines whether or not cacti have spines. Homozygous recessive nn cacti have no spines at all. -The relationship between genes S and N is an example of