LS-4 Midterm 2

Below is a pedigree from a family that lives in a population where the frequency of an autosomal recessive genetic allele is 1 in 100 (0.01). A pedigree is shown below. What is the probability that the child will have this disease.

1/10,000

In a certain population the frequency of the Tay-Sachs allele (an autosomal recessive gene) is one in a hundred (0.01). In the progeny of parents who are not related, what proportion will have Tay-Sachs disease? In the population described above, what proportion of progeny from a 1st cousin mating will have Tay-Sachs disease due to homozygosity by descent?

1/10,000 1/1,600

Manx cats are tailless and when crossed with one another produce on average 1 long-tailed (wild type) cat for every 2 Manx. The M (Manx) allele is lethal in homozygous condition due to problems arising during development. Thus, a MM genotype is lethal, a Mm cat is Manx (tailless), whereas a mm cat is wild type with a long tail. The F1 population breeds randomly among themselves, producing an F2 population. What fraction of the F2 population are Manx (have no tails)?

1/2

Manx cats are tailless and when crossed with one another produce on average 1 long-tailed (wild type) cat for every 2 Manx. The M (Manx) allele is lethal in homozygous condition due to problems arising during development. Thus, a MM genotype is lethal, a Mm cat is Manx (tailless), whereas a mm cat is wild type with a long tail. A large number of Manx cats (Mm) are put on an island and reproduce. The F1 progeny are composed of Manx and wild type cats in a 2:1 ratio, respectively. What is the allele frequency of the M allele in this F1 population?

1/3

In a particular population the allele frequency of the ABO blood type alleles are as follows: IA is 9%, IB is 90% and i is 1%. In progeny of brother-sister matings, what proportion of progeny will have blood type O?

1/400

Colorblindness is an X-linked recessive genetic trait. The frequency of the mutant colorblind allele is 1/50. What is the probability that K will be colorblind if he is male? It is not known if anyone in the family is colorblind.

1/50

Using the pedigree diagram shown below, determine the probability that the inbreeding will result in individual K being afflicted with the autosomal recessive inherited disease cystic fibrosis? The frequency of the mutant cystic fibrosis allele is 1/100. (Uncle & niece)

1/800

Below is an orphan that was born into a population where the frequency of an autosomal recessive genetic allele is 1 in 3 (0.33). Nothing is known about his/her parents. What is the probability child A will have the disease?

1/9

Within a certain island population (that is in Hardy-Weinberg equilibrium) the frequency of the L allele of the LM blood group is 0.2 and the frequency of the M allele is 0.8. There are 1000 people on the island with the following blood types: LL = 40; LM = 320; MM = 640. A virus specific for blood type M strikes the island, killing many people with blood M type. Because of this, the fitness value (W) of MM is reduced to 0.25. In the next generation, the approximate frequency of the L allele is:

38%

In a particular population the allele frequency of the ABO blood type alleles are as follows: IA is 31%, IB is 60% and i is 9%. If mating is random and the population is in Hardy-Weinberg equilibrium, approximately what percent of the population will have blood type B.

47%

Within a certain population (that is in Hardy-Weinberg equilibrium) the frequency of the L allele of the LM blood group is 0.2 and the frequency of the M allele is 0.8. This population has just been infected with a virus that kills everyone with blood type M, but individuals with blood type LM or L are unaffected by the virus. What is the allele frequency of L and M in the population after the viral infection. The allele frequency of L is:

5/9

In a particular population the allele frequency of the ABO blood type alleles are as follows: IA is 10%, IB is 50% and i is 40%. If mating is random and the population is in Hardy-Weinberg equilibrium, what percent of the population will have an A blood type. A.2% B.4% C.9% D.16% E.None of above

C. 9%

Which statement describes the swallow with the greatest evolutionary fitness? a. A swallow that lives to be 3 years old and has four offspring, two of which survive to reproduce themselves b. A swallow that lives to be 5 years old and has five offspring, one of which survives to reproduce c. A swallow that lives to be 2 years old and has four offspring, all of which survive to reproduce themselves d. A swallow that lives to be 7 years old and has three offspring, all of which survive to reproduce e. All are equally fit

c. A swallow that lives to be 2 years old and has four offspring, all of which survive to reproduce themselves

Coat color in cats is determined by a single gene in the example below: Females: 42% dark | 36% tortoise shell/calico | 22% yellow Males: 60% dark | 0% calico | 40% yellow Is the population in hardy Weinberg equilibrium?

no