Exam 14: Mendel and the Gene Idea

Use the following information to answer the questions below. Labrador retrievers are black,brown,or yellow.In a cross of a black female with a brown male,results can be either all black puppies,1/2 black to 1/2 brown puppies,or 3/4 black to 1/4 yellow puppies. -In one type cross of black × black,the results were as follows: 9/16 black 4/16 yellow 3/16 brown The genotype aabb must result in which of the following?

Use the following information to answer the questions below. Two true-breeding stocks of pea plants are crossed.One parent has red,axial flowers and the other has white,terminal flowers; all F₁ individuals have red,axial flowers.The genes for flower colour and location assort independently. -If 1000 F₂ offspring resulted from the cross,approximately how many of them would you expect to have red,terminal flowers?

Use the following information to answer the questions below. Tallness (T)in snapdragons is dominant to dwarfness (t),while red (R)flower colour is dominant to white (r).The heterozygous condition results in pink (Rr)flower colour. -If snapdragons are heterozygous for height as well as for flower colour,a mating between them will result in what ratio?

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. -A blue budgie is crossed with a white budgie.Which of the following results is not possible?

A black guinea pig crossed with an albino guinea pig produced twelve black offspring.When the albino was crossed with a second black animal,six blacks and six albinos were obtained.What is the best explanation for this genetic situation?

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?

Mendel's observation of the segregation of alleles in gamete formation has its basis in which of the following phases of cell division?

A man has extra digits (six fingers on each hand and six toes on each foot).His wife and their daughter have a normal number of digits.Having extra digits is a dominant trait.The couple's second child has extra digits.What is the probability that their next (third)child will have extra digits?

Which of the following is the best statement of the use of the addition rule of probability?

Most genes have many more than two alleles.However,which of the following is also true?

In cattle,roan coat colour (mixed red and white hairs)occurs in the heterozygous (Rr)offspring of red (RR)and white (rr)homozygotes.Which of the following crosses would produce offspring in the ratio of 1 red:2 roan:1 white?

What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants?

Which of the following describes the ability of a single gene to have multiple phenotypic effects?

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. 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?

How many unique gametes could be produced through independent assortment by an individual with the genotype AaBbCCDdEE?

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 probability that individual III-1 is Ww?

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?

Assuming independent assortment for all gene pairs,what is the probability that the following parents,AABbCc × AaBbCc,will produce an AaBbCc offspring?

Refer to the following information to answer the questions below. Humanoids on the newly explored planet Brin (in a hypothetical galaxy in ~50 years from the present)have a gene structure similar to our own,but many very different plants and animals. -One species of a small birdlike animal has an extremely variable tail length,which is a highly polymorphic trait.Geneticists have come to realize that there are eight separate genes for tail length per haploid genome,with each gene having two alleles.One allele for each gene (a,b,and so on)increases the length by 1 cm,whereas the other allele (a₂,b₂,and so on)increases it by 0.5 cm.One bird was analyzed and found to have the following genotype: A₁a₁b₂b₂c₁c₂d₁d₂e₂e₂f₁f₂g₁g₁h₁h₂ What is the length of its tail?