PD BIO 120 Final

Phenylketonuria is an inherited disease caused by a recessive autosomal allele. If a woman and her husband are both carriers, what is the probability that their first child will be a phenotypically normal girl? 1/4 1/16 1.0 3/16 3/8

3/8

Assume a particular organism has a diploid chromosome number of 4. How many different chromosome combinations can be normally packaged among the gametes of this organism? (Assume that no crossing over occurs.) 4 8 2 Infinite number 0

4

How many degrees of freedom are associated with this statistical problem? 6 5 4 3

4

If 20 individuals were alive in 1941 and the intrinsic rate of increase for this population is r = 0.05, how many individuals do you expect to be in the population in 2004? 523.4 425.0 400.1 466.7

466.7

The HOM genes of insects and the Hox genes of vertebrates are analogous because they are similar in organization, function, and composition analogous because they are due to convergent evolution homologous because they have a common origin, resulting in similarities in organization, function, and composition homologous because they are due to convergent evolution neither homologous nor analogous

homologous because they have a common origin, resulting in similarities in organization, function, and composition

The microtubular organizing center found in animal cells is an identifiable structure present during all stages of the cell cycle. Specifically, it is known as which of the following? Cell plate Centrosome Centromere Kinetochore

Centrosome

Which of these conditions are always true of populations evolving due to natural selection? Condition 1: The population must vary in traits that are heritable. Condition 2: Some heritable traits must increase reproductive success. Condition 3: Individuals pass on all traits they acquire during their lifetime. Condition 1 only Condition 2 only Conditions 1 and 2 Conditions 2 and 3 Conditions 1, 2, and 3

Conditions 1 and 2

Genetic variation, provided through sexual reproduction, offers more opportunity for offspring to survive in changing environments. What two aspects of meiosis provide sources of such variation? Mutation and fertilization Crossing over and allelic exclusion Segregation and independent assortment Crossing over and independent assortment of chromosomes

Crossing over and independent assortment of chromosomes

Mitosis is the process of chromosome separation. Cytoplasm is divided between the two daughter cells in a process known as: Karyokinesis Cytokinesis Cleavage Splitting

Cytokinesis

Wikelski and Romero (2003) found that large marine iguanas had higher reproductive success than smaller iguanas. However, the large iguanas were generally in poor body condition because they could not eat enough; at higher temperatures their foraging efficiency improved, allowing them to eat more. Thus, Wikelski and Romero hypothesize that iguana size will _______________ as global warming gradually increases air and water temperatures in the Galapagos Islands. Increase Decrease Stay the same

Increase

Your text discusses the evolution of antibiotic-resistant M. tuberculosis bacteria in a patient. Researchers discovered that the strain of M. tuberculosis taken from the dead patient has a point mutation in the rpoB gene that codes for part of the RNA polymerase enzyme. This mutant form of RNA polymerase does not normally function as well as the more common form, but the mutant rpoB gene is not affected by a commonly used antibiotic called rifampin. A researcher places M. tuberculosis isolated from the patient a year before death (no rpoB mutation) in cell cultures with M. tuberculosis isolated from the dead patient (with rpoB mutation). Half the cell cultures contain just standard nutrients, and the other cell cultures contain rifampin in addition to the standard nutrients. After many cell generations, the researcher finds that very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation. almost all M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but very few of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation. very few M. tuberculosis in any of the cell cultures carry the rpoB gene mutation. almost all of the M. tuberculosis in both types of cell cultures carry the rpoB mutation. a mix of both M. tuberculosis strains thrive in the standard cell cultures, but no living bacteria can be found in the cell cultures that contain rifampin.

very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation.

The DNA content of a diploid cell in the G-phase is x. The DNA content of a meiotic metaphase II cell from the same organism would be 0.25x 0.5x x 2x 4x

x

Gray seed color in peas is dominant to white. Assume that Mendel conducted a series of experiments where plants with gray seeds were crossed among themselves, and the following progeny were produced: 302 gray and 98 white. (a) What is the most probable genotype of each parent? (b) Based on your answer in (a) above, what genotypic and phenotypic ratios are expected in the progeny? (Assume the following symbols: G = gray and g = white.) (a) GG × gg; (b) genotypic = 3:1, phenotypic = 1:2:1 (a) Gg × Gg; (b) genotypic = 1:2:1, phenotypic = 3:1 (a) GG × Gg; (b) genotypic = 1:2:1, phenotypic = 2:1 (a) gg × Gg; (b) genotypic = 1:2, phenotypic = 3:1 (a) Gg × Gg; (b) genotypic = 3:1, phenotypic = 9:3:3:1

(a) Gg × Gg; (b) genotypic = 1:2:1, phenotypic = 3:1

What is the probability that you will roll a sum of six with the two dice? p = 0.17 p = 0.03 p = 0.14 p = 0.33

0.14

What is the probability that you will roll a six with at least one of the dice? p = 0.17 p = 0.03 p = 0.14 p = 0.33

0.33

A pig breeder has performed a series of genetic crosses and produced the following progeny in the second generation: 95 red pigs, 55 sandy pigs, and 10 white pigs. The breeder's null hypothesis is that this is a 9:6:1 ratio. He calculated a ² test statistic of _____________, and concluded that ______________. 0.69; she should not reject his null hypothesis 1.69; she should not reject his null hypothesis 6.69; she should reject his null hypothesis 7.69; she should reject his null hypothesis

0.69; she should not reject his null hypothesis

In some jacana species, males take care of the eggs and young, and females compete for territories against one to several males. Female jacanas are significantly larger than males. Which of these statements would you predict to be true of this bird species? 1. Male jacana fitness is primarily limited by ability to take care of eggs and raise young. 2. Female jacana fitness is limited by the number of males with which they can mate. 3. Variation in reproductive success should be greater in male jacanas than in females. 4. Variation in reproductive success should be greater in female jacanas than in males. 5. Males and females have equal variation in reproductive success. 1 and 3 2 and 4 1, 2, and 3 1, 2, and 4 5

1, 2, and 4

A geneticist has performed a series of genetic crosses on onions and produced the following progeny in the second generation: 126 white onions, 27 red onions, and 7 yellow onions. Her null hypothesis is that this is a 12:3:1 ratio. She calculated a ² test statistic of _____________, and concluded that ______________. 2.5; she should reject her null hypothesis 3.5; she should not reject her null hypothesis 0.5; she should reject her null hypothesis 1.5; she should not reject her null hypothesis

1.5; she should not reject her null hypothesis

A man has 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? 1/2 1/16 1/8 3/4 9/16

1/2

In establishing paternity by DNA fingerprinting, how many microsatellite repeat alleles in a child come from the father? none 1/4 1/2 3/4 all

1/2

Tightly curled hair is caused by a dominant autosomal gene in humans. This trait is rare among northern Europeans. If a curly-haired northern European marries a person with straight hair, what phenotypes (and in what proportions) are expected in the offspring? 1/2 curly (because the curly-haired individual is most likely heterozygous), 1/2 straight hair 1/2 curly (because the curly-haired individual is most likely homozygous), 1/2 straight hair All curly (because the curly-haired individual is most likely heterozygous) 3/4 curly (because the curly-haired individual is most likely heterozygous), 1/4 straight hair

1/2 curly (because the curly-haired individual is most likely heterozygous), 1/2 straight hair

A man and woman are both of normal pigmentation, but both have one parent who is albino (without melanin pigmentation). Albinism is an autosomal (not sex-linked) recessive trait. What is the probability that their first child will be an albino? 0% 1/8 1/2 1/4 100%

1/4

A man and woman are both of normal pigmentation, but both have one parent who is albino (without melanin pigmentation). Albinism is an autosomal (not sex-linked) recessive trait. What is the probability that their first female child will have albinism? 0% 1/8 1/2 1/4 100%

1/4

A man and woman are both of normal pigmentation, but both have one parent who is albino (without melanin pigmentation). Albinism is an autosomal (not sex-linked) recessive trait. What is the probability that their first child will be an albino girl? 0% 1/8 1/2 1/4 100%

1/8

A six-sided die is rolled 120 times. The results included 27 ones, 15 twos, 31 threes, 19 fours, 12 fives, and 16 sixes. Formulate a null hypothesis for a six-sided die then perform a ² test. What is the value of the test statistic? 12.8 13.8 14.8 15.8

13.8

What is the value of the test statistic for these data? 12.88 13.88 14.88 15.88

14.88

If a typical diploid somatic cell has 32 chromosomes, how many chromosomes are expected in each gamete of that organism? 32 64 16 0 46

16

What is the approximate expected probability (as a percent) of selecting the name of a girl who happens to be 4' 11.5" (59.5 inches) or shorter? 5% 2.5% 16% 32%

16%

What is the critical value for a χ² test statistic when there are seven categories at 99% confidence? 16.8 18.5 12.6 14.1

16.8

What is the expected number of students in each ethnic group based on the null hypothesis? 120 students in each ethnic group 186 African American, 84 Asian American, 168 Caucasian, 30 Native American, 132 Latin American Each ethnic group should be represented by 20% of the students 186 African American, 85 Asian American, 167 Caucasian, 29 Native American, 133 Latin American None of the above are correct

186 African American, 84 Asian American, 168 Caucasian, 30 Native American, 132 Latin American

What is the approximate expected probability (as a percent) of selecting the name of a girl who happens to be at least 5' 7" (67 inches)? 5% 2.5% 16% 32%

2.5%

What is the predicted number of individuals for each of the possible genotypes? 66.7 tall-stemmed plants, and 33.3 dwarf-stemmed plants 75 tall-stemmed plants, and 25 dwarf-stemmed plants 25 dominant homozygotes, 25 recessive homozygotes, and 50 heterozygotes 33.3 dominant homozygotes, 33.3 recessive homozygotes, and 33.3 heterozygotes

25 dominant homozygotes, 25 recessive homozygotes, and 50 heterozygotes

n tigers, a recessive allele results in white fur (virtual absence of fur pigmentation). If two phenotypically normal tigers that are heterozygous at this recessive gene are mated, what percentage of their offspring are expected to be white? 50% 75% about 66% about 90% 25%

25%

What level of confidence is associated with a width of ± 2 SD of a normal distribution? 68% 95% 99% Unknown

95%

What is an open reading frame? A gene whose function is already known. A DNA section that is thought to code for a protein because it is similar to a complementary DNA (cDNA). A DNA section that is thought to code for a protein because it has a start codon and a stop codon flanking hundreds of base pairs. Any member of a gene family.

A DNA section that is thought to code for a protein because it has a start codon and a stop codon flanking hundreds of base pairs.

An earthquake decimates a ground-squirrel population. The surviving population happens to have broader stripes on average than the initial population. If broadness of stripes is genetically determined, what effect has the ground-squirrel population experienced as a result of the earthquake? Directional selection Disruptive selection A founder event A genetic bottleneck Gene flow

A genetic bottleneck

A black guinea pig crossed with an albino guinea pig produced 12 black offspring. When the albino was crossed with a second black animal, 6 blacks and 6 albinos were obtained. What is the best explanation for this genetic situation? Albino is recessive; black is dominant. Albino is dominant; black is incompletely dominant. Albino and black are codominant. Albino is recessive; black is recessive. None of the above apply.

Albino is recessive; black is dominant.

Metaphase occurs prior to the splitting of centromeres. It is characterized by: Aligning of chromosomes at the cell's midline Splitting of centromeres Cytokinesis Disassembly of the nuclear envelope

Aligning of chromosomes at the cell's midline

In the diagram above, which of the lines represents exponential growth? Line A Line B Line C Line D All of the above

All of the above

If you were to perform a χ² test and the test statistic indicates that p < 0.05, what are you likely to conclude? You should reject the null hypothesis You should fail to reject the alternative hypothesis You should conclude that your data are nonrandom You should conclude that there is some outside influence All of the above are consistent with p < 0.05

All of the above are consistent with p < 0.05

Based on the graphs above (from the Park Grass study in Rothamsted, UK), which species declines in population over time? Tragopogon pratensis Trifolium pratense Conopodium majus All three remained stable over the time period examined.

All three remained stable over the time period examined.

What idea(s) held by Thomas Robert Malthus and included in his essay on the 'principle of population' did Charles Darwin use to justify his concept of 'struggle for existence'? Carrying capacity An 'arithmetical' increase in resources A 'geometrical' increase in population size Logistic growth An 'arithmetical' increase in resources AND a 'geometrical' increase in population size

An 'arithmetical' increase in resources AND a 'geometrical' increase in population size

What is the difference between an open reading frame (ORF) and a gene? There is no difference. An ORF is a potential gene identified by a potential protein-coding segment in DNA; a gene is a DNA segment known to produce a product. An ORF is a known protein-coding gene identified by computational means (by computer); a gene is a segment of DNA that may encode either RNA or DNA and identified by noncomputational means. An ORF is a known gene-containing DNA segment that is shorter than a full-length gene. An ORF may or may not have introns; a gene must have introns.

An ORF is a potential gene identified by a potential protein-coding segment in DNA; a gene is a DNA segment known to produce a product.

In the diagram above, which of the arrows represents the most rapid growth? Arrow B Arrow C Arrow A

Arrow B

In the diagram above, which of the arrows represents the carrying capacity? Arrow A Arrow B Arrow C

Arrow C

The nuclear membrane has to disappear in order for what to take place? Cytokinesis Attachment of mitotic spindle to kinetochores Splitting of the centrosomes Disassembly of the nucleolus

Attachment of mitotic spindle to kinetochores

Consider two populations of walking sticks found in two small Ceonothus groves. Both groves are near to patches of Adenostoma. Population A is near a large patch of Adenostoma, and population B is near a very small patch of Adenostoma. Based on your understanding of evolutionary processes, which of the following is most likely to be true of average body size in these two populations? Average body size is smaller in population A than in population B. Average body size is smaller in population B than in population A. Average body size is the same in the two populations. There is no way to make an educated guess about body size in these two populations.

Average body size is smaller in population A than in population B.

If the p-value of the resulting test statistic turns out to be p = 0.04, what conclusion is justified? The reaction time of a person driving while using a cell phone is worse than the reaction time of a person driving while not using a cell phone. The reaction time of a person driving while using a cell phone is the same as the reaction time of a person driving while not using a cell phone. Reject the null hypothesis and fail to reject the alternative hypothesis. Reject the alternative hypothesis and fail to reject the null hypothesis. Both 'a' and 'c' are correct. Both 'b' and 'd' are correct.

Both 'a' and 'c' are correct.

Zoos carefully coordinate the breeding of zoo animals, often sending animals from one zoo to mate with animals from another zoo. This practice allows zoos to what? Artificially select for preferred traits and prevent inbreeding depression. Decrease mutation rates and increase gene flow. Minimize genetic drift and maintain genetic diversity. Increase sexual selection and prevent genetic bottlenecks. Both 'a' and 'c' may be correct.

Both 'a' and 'c' may be correct.

If one wished to test the hypothesis that humans and chimps differ due to differences in the expression of a set of shared genes, the technique to use would be: Southern blotting PCR DNA sequencing protein-protein interaction assays DNA microarrays

DNA microarrays

Gill pouches in chick, human, and housecat embryos are an example of: Structural homology Developmental homology Analogy/convergent evolution The inheritance of acquired characters

Developmental homology

In what kind of population is random genetic drift most pronounced? Drift is greatest in large populations. Drift is greatest in small populations. Drift is greatest in migrating populations. Drift is greatest in fixed populations.

Drift is greatest in small populations.

After the drought of 1977, researchers hypothesized that on Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks did because they could more easily crack and eat the tough Tribulus cistoides fruits. If this hypothesis is true, what would you expect to observe if a population of these medium ground finches colonizes a nearby island where Tribulus cistoides is the primary available food in all years? (Assume that: 1. even the survivors of the 1977 drought sometimes had difficulty cracking the tough Tribulus fruits and would eat other seeds when offered a choice; and 2. food availability is the primary limit on finch fitness on this new island.) Evolution of yet larger deeper beaks over time. Evolution of smaller pointier beaks over time. Random fluctuations in beak size and shape. No change in beak size and shape.

Evolution of yet larger deeper beaks over time.

The Dunkers are a religious group that moved from Germany to Pennsylvania in the mid-1700s. They do not marry with members outside their own immediate community. Today, the Dunkers are genetically unique and differ in gene frequencies, at many loci, from all other populations including their original homeland. Which of the following likely explains the genetic uniqueness of this population? Population bottleneck and Hardy-Weinberg equilibrium Heterozygote advantage and stabilizing selection Sexual selection and inbreeding depression Mutation and natural selection Founder effect and genetic drift

Founder effect and genetic drift

Based on structures present, this cell is in which substage of interphase? S-phase G1-phase G0-phase G2-phase

G2-phase

Examine the data in the figure shown below [Sass, D. A. (1997) J. Clinical Endocrinology and Metabolism 82:1202]: Mineral apposition is enhanced by IGF-I. Bone formation is enhanced by IGF-I. GH enhances both mineral apposition and bone formation. Neither IGF-I nor GH have any significant effect.

GH enhances both mineral apposition and bone formation.

What is an important consequence of gene flow in natural populations? Gene flow increases the mutation rate among sedentary organisms. Gene flow moves individuals from one habitat to another on a seasonal basis. Gene flow tends to separate allele frequencies among populations. Gene flow tends to reduce genetic differences among populations.

Gene flow tends to reduce genetic differences among populations.

What sets genomics apart from genetics? Genomics deals with DNA sequences; genetics never considers such sequences. A goal of genomics is to understand how genes influence phenotype; genetics never considers this question. Genomics is based almost solely on studies of humans; genetics is far broader in its reach. Genomics is based on DNA sequence analysis and considers the sequence, function and interactions of many genes; genetics more often considers one or a small number of genes at a time and is generally involved in the passage of hereditary traits from one generation to the next. Genomics deals with genomes; genetics deals with gene products.

Genomics is based on DNA sequence analysis and considers the sequence, function and interactions of many genes; genetics more often considers one or a small number of genes at a time and is generally involved in the passage of hereditary traits from one generation to the next.

After telophase I of meiosis, what is the chromosomal makeup of each daughter cell? Diploid; and the chromosomes are each composed of single chromatids. Diploid; and the chromosomes are each composed of two chromatids. Haploid; and the chromosomes are each composed of single chromatids. Haploid; and the chromosomes are each composed of two chromatids.

Haploid; and the chromosomes are each composed of two chromatids.

At the end of mitosis, each daughter cell has: Twice the DNA and half the cytoplasm of the parent cell Identical DNA to that of the parent cell Half the DNA and half the cytoplasm of the parent cell Twice the cytoplasm and the same amount of DNA as the parent cell

Identical DNA to that of the parent cell

Tourist companies start visiting Island X, where the new colony of medium ground finches feeds on the tough-fruited Tribulus cistoides. The tourist companies set up reliable feeding stations with a variety of bird seeds (different types and sizes), so that tourists can get a better look at the finches. Which of these events is now most likely to occur to finch beaks on Island X? Evolution of yet larger, deeper beaks over time, until all birds have relatively large, deep beaks. Evolution of smaller, pointier beaks over time, until all birds have relatively small, pointy beaks. Increased variation in beak size and shape over time. No change in beak size and shape over time.

Increased variation in beak size and shape over time.

Why is random genetic drift aptly named? It causes allele frequencies to drift up or down randomly. It is the ultimate source of genetic variability. It is an especially important mechanism in small populations. It occurs when populations drift into new habitats.

It causes allele frequencies to drift up or down randomly.

Why is inbreeding not considered an evolutionary mechanism? It does not change genotype frequencies. It does not change allele frequencies. It does not occur often enough to be important in evolution. It is an evolutionary mechanism.

It does not change allele frequencies.

What does it mean when an allele reaches "fixation"? It is eliminated from the population. It has a frequency of 1.0. It is dominant to all other alleles. It is adaptively advantageous.

It has a frequency of 1.0.

Researchers have found fossils of Eocene horse species in Colorado. Deeper deposits contain smaller species, and more recent deposits contain larger species. How does this observation support the theory of evolution? It suggests that species are unchanging and of recent origin. It proves that environments have changed over time. It provides evidence that species change over time. It shows that all species are related to each other. It does not support the theory of evolution.

It provides evidence that species change over time.

Which statement about K (the carrying capacity) is FALSE? K varies among populations. K varies in space. K varies in time. K is specific for a given species.

K is specific for a given species.

In the diagram above, which of the lines represents the highest intrinsic rate increase (r)? Line A Line B Line C Line D

Line A

What is the null hypothesis for estimated genotypes? a 1:2:1 genotypic ratio a 3:1 genotypic ratio a 9:3:3:1 genotypic ratio a 1:3:1 genotypic ratio

a 1:2:1 genotypic ratio

Evolutionary theory predicts that species are related, not independent. Four of the following examples provide support for this prediction, but one is irrelevant. Which of the examples listed below does NOT support the claim that species are related? Many dinosaurs and other organisms went extinct following a huge asteroid impact at the end of the Cretaceous. The endostyle of lancelets (invertebrate chordates) and the thyroid gland of vertebrates develop similarly, and both produce iodinated proteins. All prokaryotes and eukaryotes use DNA to carry their genetic information. Ground squirrel species found on the North and South sides of the Grand Canyon are very similar to each other. Before synthetic insulin was available, diabetics used injections of purified pig insulin to manage their disease.

Many dinosaurs and other organisms went extinct following a huge asteroid impact at the end of the Cretaceous.

At which stage in meiosis is chromosome number typically reduced from 2n to n? Meiosis II Metaphase II Mitosis Meiosis I

Meiosis I

Homologous chromosomes move to opposite poles of a dividing cell during Mitosis Meiosis I Meiosis II Fertilization

Meiosis I

Mutation is the ultimate source of genetic variability. Why is this statement correct? DNA polymerase (the enzyme that copies DNA) is remarkably accurate. "Mutation proposes and selection disposes." Mutation is the only source of new alleles. Mutation occurs in response to natural selection. It generates the alleles that are required for a population to adapt to a particular habitat.

Mutation is the only source of new alleles.

Mendel crossed yellow-seeded and green-seeded pea plants and then allowed the offspring to self-pollinate to produce an F generation. The results were as follows: 6022 yellow and 2001 green (8023 total). The allele for green seeds has what relationship to the allele for yellow seeds? Dominant Incompletely dominant Recessive Semidominant

Recessive

In 1986 a nuclear power accident in Chernobyl, USSR (now Ukraine) led to high radiation levels for miles surrounding the plant. The high levels of radiation caused elevated mutation rates in the surviving organisms, and evolutionary biologists have been studying rodent populations in the Chernobyl area ever since. Based on your understanding of evolutionary mechanisms, which of the following most likely occurred in the rodent populations following the accident? Mutation by itself led to major changes in rodent physiology over time. Mutation led to increased genetic variation and a higher rate of evolutionary change. Mutation caused genetic drift and decreased fitness. Mutation caused the fixation of new alleles.

Mutation led to increased genetic variation and a higher rate of evolutionary change.

Left-handed people generally have a higher average IQ than right-handed people. You conduct an experiment and discover that among 20 of your close personal friends the average IQ of right-handed people is 115, while the average IQ of left-handed people is 122. The difference between these two groups is accompanied by a p-value of 0.49. Do your left-handed friends really have higher IQs than your right-handed friends? Yes No I cannot make a conclusion based on this information.

No

Crossing over usually contributes to genetic variation by exchanging chromosomal segments between Sister chromatids of a chromosome Chromatids of nonhomologous chromosomes Non-sister chromatids of homologous chromosomes Nonhomologous loci of the genome Autosomes and sex chromosomes

Non-sister chromatids of homologous chromosomes

The first gap in the cell cycle (G) corresponds to: Normal growth and functioning The period in which DNA is being replicated The beginning of mitosis The stage between DNA replication and the M phase

Normal growth and functioning

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best describes this observation? The herbicide company lost its triazine formula and started selling poor-quality triazine. Natural selection caused the pigweed to mutate, creating a new triazine-resistant species. Triazine-resistant pigweed has less efficient photosynthesis metabolism. Only triazine-resistant weeds survived and reproduced, so each year more pigweed was triazine-resistant.

Only triazine-resistant weeds survived and reproduced, so each year more pigweed was triazine-resistant.

How is plant cell cytokinesis different from animal cell cytokinesis? The cleavage furrow in animal cells is composed of protein contractile filaments; the contractile filaments found in plant cells are structures composed of carbohydrates. Plant cells form a cell plate in the middle of the cell; animal cells form a cleavage furrow. The structural carbohydrates of the plant cells separate the two cells, whereas in animal cells, a cell membrane separates the two daughter cells. Animal cells have centrosomes that are involved in this process, but plant cells have microtubular organizing centers that are not detectable during most of the cell cycle.

Plant cells form a cell plate in the middle of the cell; animal cells form a cleavage furrow.

The regular fluctuations in size of animal populations are termed what? Population cycles Population dynamics Growth factors All of the above

Population cycles

If the curves on the above diagram continue on their trajectory, what can be said about these populations? Population growth is discontinuous. Individual growth is indeterminate. Population growth is density independent. Population growth is density dependent.

Population growth is density independent.

The projections for Earth's human population by 2050 made in 1992 are much higher than those recently made in 2002. What is most likely the main difference recent history has made in this significant projection alteration? Human fertility rates have significantly decreased. Projected deaths from AIDS have significantly increased. The number of developed countries has significantly increased. All of the above answers may apply.

Projected deaths from AIDS have significantly increased.

Skeletal muscle cells can have several nuclei per cell. How does this happen? Repeated cytokinesis with no mitosis Repeated mitosis with concomitant cytokinesis Repeated mitosis without cytokinesis Multiple S-phases before the entry of a cell into mitosis

Repeated mitosis without cytokinesis

Name two evolutionarily significant benefits of meiosis that are NOT present in mitosis. Reshuffling of homologous chromosomes and crossing over Nondisjunction and homologous duplication Parity and diploidy Diploidy and haploidy

Reshuffling of homologous chromosomes and crossing over

Scientists isolate cells at various stages of the cell cycle. They find a group of cells that have 1½ times more DNA than the parent cell has during its normal growth and functioning stage. This cell is in: The process of cytokinesis The G phase of the cell cycle M phase S phase

S phase

What are minisatellites and microsatellites? Small, extrachromosomal loops of DNA that are similar to plasmids. Parts of viruses that have become integrated into the genome of an organism. Incomplete or 'dead' remains of transposable elements in a host cell. Short and simple repeated sequences of DNA.

Short and simple repeated sequences of DNA.

Synapsis is a critical event in the progression of meiosis. What is the key outcome of a completed chromosomal synapsis? Side by side alignment of non-homologous chromosomes Dyad formation Monad movement to opposite poles Side by side alignment of homologous chromosomes Chiasma segregation

Side by side alignment of homologous chromosomes

Meiosis II is similar to mitosis in that: Homologous chromosomes synapse. DNA replicates immediately before the division. The daughter cells are diploid. Sister chromatids separate during anaphase. The chromosome number is reduced following meiosis II.

Sister chromatids separate during anaphase.

Male reproductive success, measured as the number of offspring surviving to adulthood (pupating), is found for two closely related beetle species and graphed below. Which of these statements would you expect to be true of sexual dimorphism in the two species? Species A should have greater sexual dimorphism than species B. Species B should have greater sexual dimorphism than species A. Species A and B should have about equal amounts of sexual dimorphism. Neither species should show any sexual dimorphism.

Species A should have greater sexual dimorphism than species B.

Examine the figure above. What type of selection for body size appears to be occurring in these marine iguanas? Directional selection Stabilizing selection Disruptive selection Sexual selection

Stabilizing selection

A key difference between mitosis and meiosis is: Synapsis of homologous chromosomes in mitosis Synapsis of homologous chromosomes in meiosis Synapsis of nonhomologous chromosomes in mitosis Synapsis of nonhomologous chromosomes in meiosis

Synapsis of homologous chromosomes in meiosis

When gene duplication occurs to its ultimate extent, doubling all genes in a genome, what has occurred? pseudogene creation creation of a gene cluster creation of a polyploid creation of an aneuploid creation of a diploid

creation of a polyploid

Assuming graph (b) is the result of some experimental treatment, what can be concluded? The experimental treatment exacerbated the population cycling. The experimental treatment did not affect population cycling in this species. The experimental treatment has most likely identified the cause of population cycling. None of the above answers apply.

The experimental treatment has most likely identified the cause of population cycling.

Once researchers understood that chromosomes are moved by the spindle microtubules, the next question they wanted to answer is how the microtubules function to bring about this process. They used fluorescent labels to make the chromosomes and the microtubular structures fluoresce. When anaphase began (centromeres split), they photobleached a section of microtubules. As chromosomes moved toward the poles of the daughter cells, the photobleached sections of the microtubules remained stationary. This suggests that: The microtubules elongate and shorten at the centrosome end. The microtubules overlap, and slide with respect to each other, effectively shortening the microtubules without depolymerizing the actual fiber. The microtubules elongate and shorten at their kinetochore end. The microtubules are of constant length; centrosomes move farther apart to separate chromosomes.

The microtubules elongate and shorten at their kinetochore end.

A parent cell divides to form two genetically identical daughter cells in the process of mitosis. For mitosis to take place: The parent cell must first be fertilized. The parent cell must replicate its entire genome prior to mitosis. The parent cell must reproduce its DNA during telophase. The parent cell must divide its DNA in half so each daughter cell gets only the genes needed to carry out its functions. In this way, differentiation occurs.

The parent cell must replicate its entire genome prior to mitosis.

Which of the following would be a good verbal statement of a null hypothesis for this situation? The reaction time of a person driving while using a cell phone is better than the reaction time of a person driving while not using a cell phone. The reaction time of a person driving while using a cell phone is worse than the reaction time of a person driving while not using a cell phone. The reaction time of a person driving while using a cell phone is the same as the reaction time of a person driving while not using a cell phone.

The reaction time of a person driving while using a cell phone is the same as the reaction time of a person driving while not using a cell phone.

Two frog populations (same species) living in two neighboring lakes sing slightly different courtship songs. Predict what likely happens to the songs of the two frog populations after increased irrigation makes the land between the two lakes wetter. (Females prefer loud frogs to quieter frogs, but do not distinguish between the two slightly different songs. Assume that courtship song differences have a genetic basis.) The songs become more similar to each other. The songs become more different from each other. There is no change in the frog courtship songs of the two lakes.

The songs become more similar to each other.

Why are viruses, plasmids, and transposable elements viewed as selfish DNA? They are all DNAs that harm the host. They are all DNAs that replicate outside of the chromosome. They are DNAs that replicate using the host's resources without direct benefit to the host. They are all DNAs that increase in number rapidly. They all encode genes that prevent cooperation between cells.

They are DNAs that replicate using the host's resources without direct benefit to the host.

How might motor proteins assist in the process of 'pulling' chromosomes toward the poles of the cell? They split the centromere at specific arginine residues They create tension by pulling toward opposite poles They coding for enzymes involved in the process They change shape through phosphorylation or binding to ATP

They change shape through phosphorylation or binding to ATP

Based on the graphs (from the Park Grass study in Rothamsted, UK), which species increased and maintained high population size? Tragopogon pratensis Trifolium pratense Conopodium majus

Trifolium pratense

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed, no matter how often he applies triazine. Which of these actions is most likely to solve the farmer's problem? Buying triazine from a different company. Trying a different herbicide. Increasing the amount of triazine he puts on his fields. Adding triazine more often to his fields.

Trying a different herbicide.

Assuming an insert size of 160 kb, what is the minimum number of BAC clones required to cover the entire haploid human genome? about 100 about 2000 about 8000 about 19000 about 54000

about 19000

Computer scientists are indispensable in genomics research because these individuals are behind: biological modeling artificial life theory DNA sequencing bioinformatics BAC development

bioinformatics

Currently the only predators of Galapagos marine iguanas are Galapagos hawks. Iguana body size is not correlated with risk of hawk predation, although small iguanas can sprint faster than large iguanas. If predators (e.g., cats) that preferably catch and eat slower iguanas are introduced to the island, iguana body size is likely to __________ in the absence of other factors; the iguanas would then be under __________ selection. increase; directional increase; disruptive decrease; directional decrease; stabilizing stay the same; stabilizing

decrease; directional

Mutation is the only evolutionary mechanism that does little to change allele frequencies on its own always causes decreased fitness is more important in eukaryotes than in prokaryotes has no effect on genetic variation

does little to change allele frequencies on its own

In eukaryotes, the major mechanism of introducing new genes into the genome is: duplication followed by divergence lateral gene transfer pseudogene creation pseudogene restoration unequal crossing over at microsatellite repeats

duplication followed by divergence

A DNA microarray is a tool of current genomics research that owes its existence to earlier genomics investigations. What essential contribution of genomics makes microarrays possible? recently improved DNA sequencing technologies continuously improving methods of gene cloning more efficient techniques for cDNA synthesis knowledge of which DNA sequences to synthesize for the array the concept that hybridization between single-stranded nucleic acids can be used as a means of identifying any DNA sequence

knowledge of which DNA sequences to synthesize for the array

What is the initial probability of drawing a small clearie from your bag on the first draw? p = 0.12 p = 0.15 p = 0.09 p = 0.24

p = 0.09

What is the probability of drawing a small clearie from your bag on the ninth draw? p = 0.12 p = 0.09 p = 0.24 p = 0.08

p = 0.12

What is the probability of drawing a large steelie from your bag on the ninth draw? p = 0.12 p = 0.18 p = 0.24 p = 0.16

p = 0.16

What is the initial probability of drawing a large steelie from your bag on the first draw? p = 0.30 p = 0.18 p = 0.40 p = 0.24

p = 0.18

The mechanism for the spread of LINES involves some unusual elements. One of these unusual features is: translation in the cytoplasm of an mRNA that was synthesized in the nucleus the nuclear localization of RNA polymerase the transport of mRNA from the cytoplasm to the nucleus the use of an enzyme that cuts DNA the ability of reverse transcriptase to make a complementary DNA from an RNA template

the transport of mRNA from the cytoplasm to the nucleus