Midterm 1 Flashcards
1) Define biological evolution:
a. Any process by which populations of organisms change over time
b. Any change in the inherited traits of a population that occurs from one generation to the next
c. Change within a linage due to natural selection and other mechanisms
d. All of the above are possible definitions
e. None of the above is an appropriate definition
All of the above
2) Explain why Theodosius Dobxhansky said that “nothing in biology makes sense expect in the light of evolution”.
a. He was an atheist
b. He was fascinated by the capacity for evolution to explain the diversity of life and its universal biological similarities
c. He wanted to explain the origin of life
d. All of the above
e. None of the above
b. He was fascinated by the capacity for evolution to explain the diversity of life and its universal biological similarities
3) Why do baleen whales still have genes for building teeth?
a. These genes are now used to make baleen
b. Their ancestors had teeth and they inherited these genes from them, even though these genes no longer function
c. Their descendants might need teeth, so evolution keeps the genes around.
d. Evolution can’t take away genes, only add new ones
e. All of the above
f. None of the above
b. Their ancestors had teeth and they inherited these genes from them, even though these genes no longer function
What makes hemagglutinin important in the evolution of the influenza virus?
a. It allows a virus to attack the red blood cells of its host
b. It is the basic building block of virus cell walls
c. It allows the virus to bind to the cells of its host
d. All of the above are true
e. Hemagglutinin is not important to viruses
It allows the virus to bind to the cells of its host
Which of the following is a TRUE statement?
a. The ancestors of whales needed more food than could be found on land, so they evolved features that allowed them to survive.
b. Whales and humans share a common ancestor
c. Mutations always cause the improvement of a trait
d. Viruses mutate because they want to have the best adapted hemagglutinins throughout their evolution
e. All of the above are true statements
f. None of the above is a true statement
b. Whales and humans share a common ancestor TRUE
Which of the following is NOT a place that scientists look for evidence of evolution?
a. The fossil remains of extinct animals
b. Comparison of homologous traits in various species
c. Change during an individual organism’s lifetime
d. Change in populations in the wild
e. None of the above (scientists look to all of these sources)
Change during an individual organism’s lifetime
Which of these statements about phenotypes is TRUE?
a. Individuals that adjust their phenotypes in response to their environment cannot be favored by natural selection
b. Natural selection does not act on phenotypes
c. An individual’s behaviour is not part of its phenotype
d. An individual’s phenotype is a result of its genotype
e. Most phenotypes are perfectly adapted to their environments
d. An individual’s phenotype is a result of its genotype
Why do scientists overwhelming accept the theory of evolution?
a. Because the theory has overwhelmingly evidentiary support
b. Because the theory explains and predicts independent lines of evidence
c. Because scientists have tests and retested predictions
d. Because a scientific theory is a comprehensive explanation of many diverse observations.
e. All of the above
All of the above
What did early scientists learn from fossils?
a. The earth changes
b. The history of an area can be found in its rocks
c. Organisms different from current organisms once lived on the plant
d. Marine fossils can be found on mountain tops
e. All of the above
f. None of the above
All of the above
10) Which of these statements is a concept found in George Buffon’s idea about evolution but, not in the way we understand evolution now?
a. Populations can change overtime
b. Life is divided into a number of distinct types that are not related to each other
c. Living things are made of the same particles found in rocks and water
d. Life took more than a few thousand years to evolve
e. All of the above
f. None of the above
b. Life is divided into a number of distinct types that are not related to each other
What would Jean-Baptiste Lamarck and Charles Darwin have agreed upon?
a. One generation can pass on its traits to the next
b. Individual animals and plants can adapt to their environment
c. Life was driven from simplicity to complexity
d. Both a and b
e. All of the above
f. None of the above
One generation can pass its traits on to the next
What is a correct definition of homology?
a. Common traits due to shared inheritance from a common ancestor
b. Common function of traits due to similar usage
c. Structure of lings that are common among all mammals
d. All of the above
e. None of the above
Common traits due to shared inheritance from a common ancestor
What set Darwin and Wallace’s concept of natural selection apart from earlier ideas of evolution?
a. Their concept explains why organisms were related to each other
b. Their concept depended on a process that is observable
c. Their concept depended on the inheritance of characteristics from one generation to the next
d. Their concept suggested that change was very gradual
e. All of the above (all of these ideas were new).
f. None of the above (these ideas were shared by earlier views).
Their concept depended on a process that was observable
Did Charles Darwin invent the Theory of Evolution?
a. Yes. On the Origin of Species outlines the theory of evolution as scientists understand it today
b. Yes. The theory of evolution is based entirely on natural selection, which was Darwin’s idea.
c. No. Natural selection and evolution were theories long before Darwin wrote On the Origin of Species
d. No. Darwin described a mechanism for evolutionary change, but natural selection is only a component of the theory of evolution.
No. Darwin described a mechanism for evolutionary change, but natural selection is only a component of the theory of evolution.
What evidence did Darwin use to predict the age of the Earth?
a. Darwin didn’t predict the age of the Earth
b. Darwin couldn’t predict the age of the Earth, because he didn’t understand radioactive decay.
c. Darwin used processes he could observe, such as erosion and sedimentation, to predict that the Earth must be hundreds of millions of years old.
d. It doesn’t matter, because Lord Kelvin refuted Darwin’s evidence
Darwin used processes he could observe, such as erosion and sedimentation, to predict that the Earth must be hundreds of millions of years old
What is an isochron?
a. The ratio of rubidium (Rb) to strontium (Sr)
b. The half-life of an isotope
c. The slop of the line describing the ratio of 87Sr to 86Sr
d. A line on a graph of isotope ratios that indicates mineral samples formed at a similar time
A line on a graph of isotope ratios that indicates mineral samples formed at a similar time
Which isotope would be useful for dating a fossil found in relatively recent sediments?
a. An isotope with moderately high probability of decay
b. An isotope with a low probability of decay
c. Rubidium
d. Strontium
e. Any unstable isotope would be useful
An isotope with moderately high probability of decay
How did the fossils of the Burgess Shale form?
a. The animals fell to the bottom of a deep lake and over thousands of years turned to rock
b. The animals dropped into anoxic ocean depths and were covered by fine sediment
c. The animals were rapidly covered by ash falling from a volcano
d. Both a and b
The animals dropped into the anoxic depths and were covered by fine sediment
How did scientists determine that Tyrannosaurus res could not run very fast?
a. They compared skeletal structures of T-rex to modern animals to determine the size of its muscles
b. They used living animals to test a model they had developed on the biomechanics of running
c. They used evolutionary theory to determine the most closely related organism to the T-rex
d. They developed a biomechanical model of running animals to determine how much force leg muscles of a given size could generate
e. All of the above
All of the above
Which outcome would you predict if you could compare the isotopes of fossils of two species of human ancestors and found high ratios of carbon-13/carbon-12 in one and low ratios in the other?
a. The species with high ratios likely lived in grasslands
b. The species with high ratios likely preferred eating shrubby vegetation
c. The species with high ratios likely ate a mixed diet
d. It would depend on what kind of human fossils
e. All of the above
f. None of the above
The species with high ratios would likely ate a mixed diet
What independent lines of evidence have scientists used to determine the history of life on Earth?
a. Zircons
b. Behaviour of living species
c. Fossilized dung
d. Oxygen isotopes
e. All of the above
All of the above
Which group is not considered one of the major lineages of all living organisms?
a. Bacteria
b. Microbes
c. Archaea
d. Eukarya
Microbes
) How can scientists determine that multicellular life arose more than once
a. Animals are more closely related to single-celled eukaryotes than to fungi
b. Fungi can produce multicellular structures
c. Bacteria live as multicellular groups called biofilms
d. Scientists have no idea if multicellular life arose more than once.
Animals are more closely related to single-celled eukaryotes than to fungi
Define prokaryotes:
a. A descriptive grouping for microorganism that lack membrane-bound organelles
b. A grouping useful in the classification of earlier microbes
c. A grouping often used instead of Archaea
d. A single-celled eukaryote
e. A grouping to describe early fossils of plants
A descriptive grouping for microorganism that lack membrane-bound organelles
) Why is a notochord an important adaptation for understanding the evolution of humans?
a. The development of a notochord occurred in early fish
b. A notochord is a backbone
c. A notochord is a characteristic of chordates
d. A notochord serves to distinguish the Ediacaran family from the trilobites.
A notochord is a characteristic of chordates
What allows us to know that synapsids were tetrapods?
a. They lived on land
b. They were dominant land animals
c. They evolved to mammals
d. They had four legs they used for walking
e. All of the above
They had four legs they used for walking
Which of the term is not associated with treelike depictions of evolutionary histories known as phylogenies?
a. Node
b. Seed
c. Branch
d. Root
Seed
If you were looking at a phylogeny of living bird species, where could you find the name of a species on non-theropod dinosaur?
a. At the tip of a branch, as an outgroup
b. At the root of the tree
c. Either a or b
d. None of the above
At the tip of a branch, as an outgroup
At the root of the tree
Either A or B.
Which is NOT a synapomorphy?
a. The ability to swim in dolphins and sharks
b. The production of milk in humans and cats
c. The ability to fly in eagles and pigeons
d. The laying of eggs with shells in snakes and lizards
e. All of the above are synapomorphies
The ability to swim in dolphins and sharks
Which of the following is an example of homoplasy?
a. The reversion of a derived character state to its ancestral state
b. The independent origin of similar traits in separate lineages
c. The evolution of winds in both birds and bats
d. All of the above
e. None of the above
All of the above
Why are bird feathers considered an exaptation?
a. Because they are shared derived character found in most birds
b. Becayse they are traits that have independently evolved into separate lineages
c. Because they first evolved for functions other than flight
d. Because they are an evolutionary reversal to an ancestral character state
Because they first evolved for functions other than flight.
) If two individuals mate, one of them heterozygous at a locus (one dominant and one recessive allele) and the other homozygous for a recessive allele at the same locus, what will be the outcome?
a. The offspring will be either heterozygous, or homozygous, for the recessive allele
b. The offspring will either be homozygous for the dominant allele, heterozygous, or homozygous for the recessive allele
c. The offspring will not evolve, because they will carry the same alleles as the parents
d. The recessive allele eventually will become dominant in the population
e. None of the above
The offspring will be either heterozygous, or homozygous, for the recessive allele
The Hardy-Weinberg theorem is an important mathematical proof because
a. It demonstrates that dominant alleles are more common than recessive alleles
b. It demonstrates that in the absence of outside forces, allele frequencies of a population will not change from one generation to the next
c. It demonstrates that heterozygotes are always better
It demonstrates that in the absense of outside forces, allele frequencies of a population will not change from one generation to the next.
Which population would be most likely to have allele frequencies in Hardy-Weinberg equilibrium?
a. A population in a rapidly changing environment
b. A population where immigration is common
c. A large population that currently is not evolving
d. A population that cycles between a very large and very small number of individuals
A large population that is currently not evolving.
A genetic bottleneck in a population often results in what?
a. Loss of alleles
b. Loss of genetic diversity
c. An increase in genetic drift
d. All of the above
e. None of the above
All of the above
What do population geneticists mean when they refer to the fitness of an allele?
a. The ability of the allele to survive in a population
b. The contribution of an allele to the strength and over-all health of a genotype
c. The contribution of an allele to a genotype’s relative success at producing new individuals
d. Whether an allele is dominant or not
e. Whether an allele is recessive or not
The contribution of an allele to a genotype’s relative success at producting new indivduals
If a mutation that produces a new deleterious allele arises in a population, what will most likely happen to the frequency of that allele?
a. It depends on that allele’s effect on the phenotypes – if the allele is recessive, it can remain at a low frequency within the population for a very long time
b. It depends on the allele’s effect on the phenotypes – if the allele is recessive, drift will determine whether it persist in the population
c. The allele will be rate enough that it almost never occurs in a homozygous state
d. Deleterious alleles are always quickly purges from populations
e. A, b, c
A, B, C
) If Cavalli-Sforza and colleagues had measured allele frequencies as 0.869 for the A allele and 0.131 for the A allele, how many homozygous genotypes should they have expected to find? Would they have considered the population to be at equilibrium?
a. 9354 AA and 29 SS. No, they would not have considered the population to be at equilibrium
b. 9354 AA and 211 SS. Yes, they would have considered the population to be at equilibrium
c. 9354 AA and 211 SS. No, they would not have considered the population to be at equilibrium
d. 2811 AA and 2993 SS. No, they would not have considered the population to be at equilibrium
e. 9527 AA and 187 SS. No, they would not have considered the population to be at equilibrium
c. 9354 AA and 211 SS. No, they would not have considered the population to be at equilibrium
) What can measuring genetic distance, or Fst, tell scientists about a group of organisms?
a. Whether groups have begun to diverge from each other
b. Whether genes are under strong selection
c. How barriers may be influencing gene flow
d. All of the above
e. None of the above
All of the above
Phenotypic traits often have a continuous distribution because
a. They are a result of dominance interaction
b. They are not related to genotypes
c. They are influenced only by the environment
d. They are often polygenic
They are often polygenic
The breeder’s equation incorporates two of the conditions Darwin identified that must be met for evolution by natural selection to take place. Which two?
a. Greater survival (S) and reproduction (K) of phenotypes with specific alleles
b. Variation in phenotypic traits (R) and heritability of additive alleles (h^2)
c. Differences in phenotypes that influence the probability of survival or reproduction (S) and differences in phenotypic traits that must be at least partially heritable (h^2)
d. Heritability of additive alleles (h^2) and the evolutionary response of the population (R)
e. None of the above statements demonstrate evolution by natural selection
Differences in phenotypes that influence the probability of survival or reproduction (S) and differences in phenotypic traits that must be at least partially heritable (h^2)
How can scientists determine what constitutes a quantitative trait locus?
a. They painstakingly examine the genotypes of hundreds of individuals and look for genes that are consistently similar
b. They examine nucleotide sequences and count the repeated segments that they feel are important
c. They hybridize species and compare how genetic markers recombine in the offspring
d. They select for different traits in lineages of an organism, cross-breed the lineages for two generations, and search for genetic markers that are correlated with expression of the trait
e. They map the genome and identify the distinct, short segments of DNA markers such as single nucleotide polymorphisms (SNPs), simple sequence repeats, and transposable elements.
They select for different traits in lineages og an organism, cross-breed the lineages for two generations, and search for genetic markers that are correlated with expression of teh trait
If the age of sexual maturation is a phenotypically plastic trait, what relationship(s) would you expect to find?
a. Genotypes differ in age at which they reproduce
b. Environmental conditions (such as nutrition) affects the age at which individuals begin reproducing
c. Body size affects the age at which different genotypes reproduce
d. All of the above
e. None of the above
Environmental conditions (such as nutrition) affects the age at which individuals begin reproducing
Which of the following is an example of the process of evolution?
a. A population of snowshoe hares having different frequency of alleles than the previous generation
b. Tree dropping their leaves in the fall
c. A man becoming immune to a strain of virus that caused him to have a cold when he was younger
d. A female bird laying more eggs one season that she did three previous seasons combined
e. All of the above are examples of the process of evolution
A population of snowshoe hares having different frequency of alleles than the previous generation
Which of the following statements about natural selection is true?
a. Natural selection is the same as evolution
b. Natural selection always results in reduced genetic variation
c. Natural selection can have an evolutionary effect only if phenotypic differences are heritable
d. Natural selection acts directly on genotypes
e. Changes in allele frequencies can occur only because of natural selection
Natural selection can have an evolutionary effect only if phenotypic difference are heritable
For a gene with two alleles and p=02, the frequency of heterozygotes would be:
a. 0.009
b. 0.42
c. 0.32
d. 0.49
e. Not enough information
0.32
The response of a quantitative character to selection depends on the heritability (h^2) of the character and the selection differential (S). Response (R) to selection will be greatest and selection, respectively, which of the following? R=h^2(5)
a. 0.75; 4
b. 0.40; 2.5
c. 0.75; 2.5
d. 0.40; 4
e. 0.60; 4
0.75; 4
For a locus with two alleles, the maximum heterozygosity would be when:
a. p=q
b. p>q
c. q>p
d. p=0
e. q=0
p=q
The proportion of phenotypic variance that is due to additive genetic differences among individuals is referred to as:
a. non-additive genetic components
b. environmental variance
c. broad sense heritability
d. narrow sense heritability
e. linkage disequilibrium
narrow sense heritability
Which of the following represents the phenotypic variance (Vp) in a phenotypic trait?
a. VG+VA
b. VA+VE
c. VD+VE
d. VG+VD
e. VG+VE
VP=VG+VE
Which of the following involve assumption for the Hardy-Weinberg principle?
a. Heterozygosity = 2pq
b. q=1-p
c. p^2+2pq+q^2=1
d. two or all of A, B, C
e. none of A, B, C
two or all of A, B, and C.
The data from morality rate of offspring from marriage registered in 1903-1907 in Italian populations indicated that the offspring of related individuals have higher mortality rates. What is a likely cause of this inbreeding depression?
a. Close relative are more likely to neglect their children
b. Italian populations are more likely than other populations to have genetic disease
c. Inbred individuals are more likely than other individuals to be homozygous for deleterious recessive alleles
d. The offspring of close relatives are born at large size than other offspring
e. Italians are more likely to mate with other Italians than with individuals of other nationalities
Inbred individuals are more likely than other individuals to be homozygous for deleterious recessive alleles
Differences in the number of mates or in the reproductive capacity of individuals of one sex can be explains by the concept of:
a. Reproductive assurance
b. Sexual selection
c. An operational sex ratio
d. Sex-role reversal
e. Sperm competition
Sexual selection
A genetic polymorphism results in two different morphs in a population. With frequency-dependent selection, genetic variation is maintained because:
a. One morph has a higher frequency when its rare
b. One morph has a lower frequency when its rare
c. One morph has a higher frequency when its common
d. Two or all of A, B, C
Two or all of A, B, and C
The additive genetic variance of fiddler crab claws is 0.50, while the total phenotypic variance is 0.30. What is the heritability of this trait?
a. 1.6667
b. 0.6
c. 0.625
d. 0.2
e. 0.5
1.6667
Artificial selection experiments almost always show a response to selection. What is the most likely explanation for this observation?
a. Populations contain significant amounts of genetic variation
b. Few traits are polygenic
c. Laboratory populations often are inbred
d. Mutations are rare
e. Alleles are in lineage disequilibrium
Populations contain significant amounts of genetic variation
Imagine a species distributed over a large geographic range containing a gradual environmental gradient and having different genotypes with greater fitness at opposite ends of the range. Which of the following patterns would you expect to find for the frequencies of genes over the entire range in the absence of gene flow?
a. There will be a very gradual cline
b. There will be a peak shift
c. There will be a step cline
d. One genotype will become fixed for the entire population
e. Each genotype will be found at random frequencies at various points along the range
There will be a very gradual incline
Explain what is required for natural selection to occur. A) Heritable variation B) Fitness differences C) Mutation D) Random genetic drift E) A and B F) A and B and C G) A and B and C and D
Heritable variation
Fitness differences
Natural selection acts on existing traits that may increase fitness in new environments
1) True
2) False
True
The snow goose (Chen caerulescens) has both a blue and white morph. Inheritance is Mendelian: BB and Bb individuals are blue, while bb individuals are white. If 16 geese in a population of 100 are white and 84 are blue, how many of the blue geese would you expect to be carriers of the b allele (i.e., Bb heterozygotes)? HINT: BB and Bb = 84 blue geese bb = 16 white geese (p2 + 2pq) = 84/100 (q2 ) = 16/100
Total = 100
a) 52
b) 48
c) 84
d) 36
e) 16
48
For a locus with 2 alleles, the maximum heterozygosity would be when:
a) p = q
b) p > q
c) q > p
d) p = 0
e) q = 0
p=q
Which of the following would define a polymorphic locus?
a) p = 1.0
b) q = 0.0
c) p = q
d) p + q = 1.0
e) more than one of a, b, c, d
p=q
For a gene with two alleles and p = 0.3, the frequency of heterozygotes would be:
a) 0.09
b) 0.42
c) 0.21
d) 0.49
e) not enough information
0.42
Which of the following observations would not violate the assumptions of the Hardy-Weinberg principle?
a. UV radiation induces new mutations at a high frequency.
b. Individuals migrate from nearby populations but die prior to breeding.
c. Cold tolerance differs by genotype, and the population experiences a frost.
d. Inbreeding is present.
Individuals migrate from nerby populations but, die prior to breeding
You have sampled a population in which you know that the percentage of the homozygous recessive genotype (aa) is 36%. Using that 36%, calculate the percentage (%) of the “AA” genotype.
16%
What allelic frequency (p) will generate twice as many recessive homozygotes as heterozygotes?
Hint:
Freq. (AA) = p2
Freq. (Aa) = 2pq
Freq. (aa) = q2 (recessive)
twice as many recessive homozygotes as heterozygotes:
q2 = 2 x (2pq)
a) p = 0.2
b) p = 0.4
c) p = 0.8
d) p = 1.0
p=0.2
An allele with a frequency of q = 0.0001 is likely to be recessive and deleterious (harmful).
True
False
False
For a gene with two alleles and p = 0.2, the frequency of heterozygotes would be:
a) 0.09
b) 0.42
c) 0.32
d) 0.49
e) not enough information
0.32
Which of the following observations would violate the assumptions of the Hardy-Weinberg principle?
a. No mutation
b. Individuals migrate from nearby populations but die prior to breeding.
c. Cold tolerance differs by genotype, and the population experiences a frost.
d. Random mating
e. Population size is very large.
Cold tolerance differs by genotype, and the population experiences a frost
You have sampled a population in which you know that the percentage of the homozygous recessive genotype (aa) is 36%. Using that 36%, calculate the percentage (%) of the “Aa” genotype.
48%
An allele with a frequency of q = 0.0001 is likely to be recessive and deleterious (harmful).
True
False
False
Random mating can avoid the loss of genetic variation in small populations.
True
False
False
Inbreeding depression is likely caused by recessive deleterious mutations made homozygous.
True
False
True
A population with allele frequencies p = 0.30 and q = 0.70 has an inbreeding coefficient of F= 0.50. The observed frequency of heterozygotes is:
(Note: F = (Hexp – Hobs)/ Hexp )
a) 0.500
b) 0.300
c) 0.105
d) 0.210
e) 0.700
f) none of the above
0.210
Migration and gene flow can change allele frequencies but not genotype frequencies.
True
False
False
Finite population size causes:
a) allele frequencies to diverge among populations
b) a reduction in heterozygosity
c) random drift of allele frequencies
d) an increase in homozygosity
e) all of a, b, c, d
f) more than one of a, b, c, d
all of a, b, c, d
