Exam 2 quizzes Flashcards
With which of the following statements concerning Huntington’s disease would you agree?
A) Huntington’s disease causes degeneration of tissue in the brain.
B) You would agree with more than one of these.
C) If both parents have Huntington’s disease, the children have a 50% chance of having the Huntington’s gene.
D) You would agree with all of these.
E) Although Huntington’s disease is always lethal, it persists in the human population because it usually is not expressed until after reproduction.
the correct answer is You would agree with more than one of these.
Once transcription has been completed, which component is not necessary for protein synthesis to proceed?
ribosomes
tRNA
DNA
mRNA
amino acids
DNA
Below is a pedigree for a hereditary disease that causes progressive muscle atrophy. What is the most likely mode of inheritance of this disease?
B) Sex-linked recessive
Which of the following is true of cystic fibrosis (CF)?
A. CF causes secretions to be thinned.
B. CF is caused by mutations in both copies of the CFTR gene.
C. CF makes cells unable to manage sodium.
D. There is no testing for CF, which is why it is so prevalent in white populations.
E. If a mother has CF and has children with a male who is a non-carrier and does not have the disease, half of her children will be carriers.
B. CF is caused by mutations in both copies of the CFTR gene.
Which is true of mutations?
A) More than one of these are correct.
B) A nonsense mutation involves a base substitution that causes a “stop” codon to form
C) A frameshift mutation always changes multiple amino acids
D) A missense mutation can result in either an insignificant or significant change in a protein
E) A mutation on the third base pair of the codon is more likely to change the amino acid than a mutation on the first base pair.
A) More than one of these are correct.
Which of the following examples are consistent with Lamarck’s theory of evolution and which are consistent with Wallace’s theory of evolution?
Example 1. Some Daphnia in a pond population are resistant to a pathogen. When there is an outbreak of the pathogen, resistant Daphnia are better able to survive and reproduce compared to the non-resistant Daphnia. This results in more resistant Daphnia in the offspring generation.
Example 2. Sea otters break open mussels to eat by hitting them on hard rocks. Sea otters get stronger as they get older and eat more mussels, and they pass on these strong muscles to their offspring.
Example 3. Your garden has a resident snail population with some dark green snails and some white snails. Birds eat snails that they can find. Planting dark green plants in your garden resulted in a greater proportion of dark green snails in the offspring generation.
Lamark: 1; Wallace: 2,3
None of the above combinations are correct.
Lamark: 1, 2, 3. Wallace: none
Lamark 2; Wallace 1,3
Lamark: 2, 3; Wallace 1
Lamark 2; Wallace 1,3
The evolutionary concepts of Darwin and Wallace rest on several premises. Which of the following premises did Darwin and Wallace propose?
A) All of these are true.
B) More than one of these are true.
C) There are chance variations among individual organisms in a population, some of which are heritable.
D) Dominant alleles and phenotypes always make organisms more fit for their environment.
E)In most species, more individuals are produced in each generation than survive and reproduce.
B) More than one of these are true.
A small population of frogs in a local wetland has high migration to and from the wetland in spring. Which is true of this frog population and Hardy-Weinberg (H-W) equilibrium?
A)H-W is only useful for tracking allele frequencies in invertebrates (like mosquitoes) and would not be applicable to frog populations.
B)None of these are true.
C)The population meets H-W assumptions since the frogs are unlikely to have new mutations.
D)Spring frog migration helps maintain H-W equilibrium and thus this population meets H-W assumptions.
E)While the population does not meet H-W assumptions, calculating H-W proportions could tell us if some alleles change in frequency over time.
E)While the population does not meet H-W assumptions, calculating H-W proportions could tell us if some alleles change in frequency over time.
In a population that is in Hardy-Weinberg equilibrium, 49% of the population show the recessive homozygote genotype. What is the frequency of heterozygous individuals?
A) 0.42
B) 0.21
C) 0.09
D) 0.70
E) 0.51
A) 0.42
Natural Selection:
A) Acts on genotypes of existing mutations
B) Promotes the production of new mutations
C) Drives organisms to perfection over time
D) Inhibits the production of new mutations
E) Acts on phenotypes of existing mutations
E) Acts on phenotypes of existing mutations
In frogs, the dominant allele at one locus increases frog’s resistance to a common and deadly fungal pathogen. A pond hosts a large frog population where the dominant allele has been common over the course of many years (frequency = 0.9). One year, there is a severe drought in late spring and early summer which dries and kills almost all of the frogs’ egg masses. After the drought, the frog population is very small (~48 frogs). As the frog population begins to grow again, the dominant allele has a frequency of 0.48. What force most likely changed the frequency of the dominant allele?
A) Genetic drift altering allele frequencies
B) Gene flow introducing novel alleles
C) Natural selection for the dominant allele
D) Random mating increases the recessive allele’s frequency
E) Mutation at the loci increased the frequency of the recessive allele
Genetic drift altering allele frequencies
Eastern and Western Spotted Skunks overlap in their geographical range, but because of the difference in peak breeding time, they do not interbreed. This isolating mechanism is:
Ecological; Prezygotic
Temporal; Postzygotic
Ecological; Postzygotic
Temporal; Prezygotic
Behavioral; Prezygotic
Temporal; Prezygotic
The finches of the Galapagos Islands have been studied by evolutionary biologists for many years. Which statement(s) is/are true concerning the evolution of these fascinating finches?
There are 16 islands with finches, and all island finches form a single large gene pool that is separate from the mainland finch gene pool.
More than one of these are true.
The finches underwent an adaptive radiation as finch species evolved to exploit various habitats and food sources on the different islands.
Secondary contact between a seed eating finch and an insect eating finch would likely result in extinction of one species due to resource competition.
Differences in body size prevent allopatric finch species from fusing back into one species.
The finches underwent adaptive radiation as finch species evolved to exploit various habitats and food sources on the different islands.
Consider a small population of fish occupying a river section that is isolated from other populations by upstream and downstream dams. Which of the following management efforts could help increase the genetic variation present in that population?
Removing the largest juvenile fish from the population to ensure that there are enough food resources for the rest of the population
Breeding a small number of adults in a hatchery to ensure that their offspring survive at higher rates than in the natural environment, and releasing large numbers of related offspring back into the population
Two of these are true.
All of these are true.
Removing one of the dams to allow for interbreeding with another small population
Removing one of the dams to allow for interbreeding with another small population
