Exam 2

The difference in sizes between male and female gametes results from two unequal divisions of __________________ in female gamete development. A)Cytoplasm B)DNA C)Chromosomes D)Mitosis E)nuclei

A)Cytoplasm

When genetically based traits are inherited independently from each other, this is known as: A)Mendel's law of independent assortment. B)linkage. C)pleitropy. D)polygenism. E)multi-allelism.

A)Mendel's law of independent assortment.

Which of the following pairings, indicated by letters referring to blood type phenotypes, CANNOT produce a child with type B blood? A)O AB B)A B C)O O D)B O E)All of the above could produce a child with type B blood.

A)O AB

A given section of DNA with the sequence AATGGCTAT is transcribed. What is the corresponding sequence on the mRNA transcription? A)UUACCGAUA B)TTACCGATA C)CCGTTAGCT D)UUGAACGUA E)GGTAACTGT

A)UUACCGAUA

The law of segregation states that: A)each of two alleles for a given trait segregates into different gametes. B)an allele on one chromosome will always segregate from an allele on a different chromosome. C)the transmission of genetic diseases within families is always recessive. D)gametes cannot be separate and equal. E)the number of chromosomes in a cell is always divisible by 2.

A)each of two alleles for a given trait segregates into different gametes.

A situation in which the heterozygote offspring of two homozygotes show a phenotype intermediate between those of the parents is called: A)incomplete dominance. B)multiple allelism. C)a test-cross. D)a single-gene trait. E)heterozygote superiority.

A)incomplete dominance.

A comparison of the graphs in the figure from question 15 shows that: A)males maximize reproductive success by mating with as many females as possible. B)females maximize reproductive success by mating with as many males as possible. C)females maximize reproductive success by mating with as few males as possible. D)males minimize reproductive success by mating with as many females as possible. E)both males and females maximize reproductive success by mating as much as possible.

A)males maximize reproductive success by mating with as many females as possible.

The appropriate unit for defining and measuring genetic variation is the: A)population. B)species. C)family. D)atomic. E)individual.

A)population.

Kin selection is defined as: A)selection for a behavior that lowers an individual's own chances of survival or reproduction, but raises those of a relative. B)selection that operates not just on one individual, but on all of its relatives as well. C)selection for a behavior that raises an individual's own chances of survival or reproduction, as well as those of a related individual. D)selection for a behavior that lowers an individual's own chances of survival or reproduction, but raises those of another individual who may be reciprocally altruistic. E)None of the above is correct.

A)selection for a behavior that lowers an individual's own chances of survival or reproduction, but raises those of a relative.

The purpose of mitosis is to enable existing cells: A)to generate new, genetically identical cells. B)to generate gametes. C)to generate new, genetically diverse cells. D)to die on purpose. E)to grow.

A)to generate new, genetically identical cells.

The egg cells of a horse contain 32 chromosomes. How many chromosomes are in the horse's liver cells? A)16 B)64 C)8 D)128 E)32

B)64

Which of the following statements is NOT correct of human sex chromosomes? A)Gametes produced by females have an X chromosome, but not a Y. B)All diploid cells have both an X and a Y chromosome. C)All diploid cells have at least one X chromosome. D)On average, half a man's sperm carry an X chromosome and half carry a Y. E)X and Y chromosomes differ in structure.

B)All diploid cells have both an X and a Y chromosome.

What is the ultimate explanation for modern human preference for fatty foods? A)We do not actually prefer fatty foods; we prefer sugary foods. B)Ancestral humans who preferred fatty foods were less likely to starve, leaving more offspring in the next generation. C)When we eat fatty foods, taste receptors on our tongue are stimulated, sending an action potential to our brain triggering the "do-it-again" centers. D)We like the way that lipid-rich foods taste. E)Fatty foods have nine calories per gram, unlike carbohydrates and proteins, which have four calories per gram, and in our environment we need to maximize our caloric intake in order to maximize our fitness.

B)Ancestral humans who preferred fatty foods were less likely to starve, leaving more offspring in the next generation.

When a goose spots an egg outside of its nest, the goose gets out of the nest and rolls the egg back. Once started, a goose continues the egg-retrieval movement all the way back to the nest, even if the egg is taken away during the process. This is called: A)step-wise reproductive collaboration. B)a fixed action pattern. C)ornithological canalization. D)prepared learning. E)supernormal stimulus.

B)a fixed action pattern.

Whether it is eggs or sperm being produced through meiosis, under normal circumstances, each gamete ends up with: A)exactly two copies of each chromosome. B)exactly one copy of each chromosome. C)equal amounts of cytoplasm. D)the same number of spindle fibers. E)the same alleles.

B)exactly one copy of each chromosome.

For a population to evolve through natural selection: A)the mutation rate must be low. B)its members must possess inheritable variation. C)it must be in an unstable environment. D)individuals must be migrating in and out of the population. E)it must have a small population size.

B)its members must possess inheritable variation.

The sex with the greater energetic investment in reproduction will be ___________________ when it comes to mating. A)more discriminating B)less discriminating C)less interested D)more exhaustive E)more competitive

B)less discriminating

In humans, genes make up ______ of DNA. A)about 50% B)less than 5% C)100% D)about 10% E)about 75%

B)less than 5%

In a particular population, over the course of several dozen generations, an adenine was replaced by a guanine at a particular non-coding locus in the DNA base sequence. The evolutionary mechanism responsible for this change was: A)migration. B)mutation. C)directional selection. D)genetic drift. E)disruptive selection.

B)mutation.

Sexual dimorphism refers to: A)sexually reproducing species in which males are larger than females. B)the situation in which males and females differ physically and/or behaviorally. C)the situation in which males and females have identical genitalia. D)sexually reproducing species in which females are larger than males. E)species with iteroparous (or "big bang") reproduction.

B)the situation in which males and females differ physically and/or behaviorally.

When individuals of any species find themselves in an environment that differs from the environment to which they are evolutionarily adapted, we observe that: A)they become a new species. B)they engage in behaviors better fit to the environment the individual organisms find themselves in than to the environment the species evolved in. C)they migrate back to the environment to which they are evolutionarily adapted. D)they die out rapidly. E)they engage in behaviors better fit to the environment the species evolved in than the environment the individual organisms find themselves in.

B)they engage in behaviors better fit to the environment the individual organisms find themselves in than to the environment the species evolved in.

The mechanism by which the information contained in DNA is coded into a complementary RNA copy is called: A)the one gene-one enzyme hypothesis. B)transcription. C)the central dogma. D)replication. E)translation.

B)transcription.

Bt corn is a genetically engineered plant. What feature gives it value as a crop plant? A)The plant produces a toxin designed to kill corn borers. B)The plant produces a toxin designed to kill monarch butterflies. C)The plant grows significantly larger ears of corn. D)The plant produces a toxin designed to kill competing plants (also known as weeds). E)The plant produces better-tasting fruits.

C)The plant grows significantly larger ears of corn.

What are the two major methods of cellular division in eukaryotic cells? A)meiosis and cloning B)fission and cloning C)meiosis and mitosis D)meiosis and fission E)mitosis and cloning

C)meiosis and mitosis

Sex-linked traits: A)are coded for by genes on the Y chromosome only. B)occur in males but not females. C)often are expressed in different frequencies in males and females. D)are coded for by genes on the autosomes. E)occur in females but not males.

C)often are expressed in different frequencies in males and females.

Brassica oleracea was a European wild plant. Early farmers were able to use artificial selection on this plant to produce cabbage, brussels sprouts, kohlrabi, kale, broccoli, and cauliflower. This diversification through selection was possible because: A)artificial selection is always possible, whereas natural selection requires much larger population sizes. B)wild plants respond to artificial selection in situations when domesticated plants cannot. C)the species contained large amounts of genetic variation. D)artificial selection does not require differential reproductive success, whereas natural selection does. E)exotic species are always more adaptable than the native species in an area.

C)the species contained large amounts of genetic variation.

Alternate versions of a gene can code for different ________________ of the same character. A)bases B)Traits C)gametes D)Alleles E)chromosomes

D)Alleles

Errors sometimes occur when DNA duplicates itself. Why might that be a good thing? A)Errors in DNA replication can never be a good thing. B)The rebuilding process proceeds much more quickly when a few errors occur. C)Most errors are, in fact, good for the organism in which they occur. D)New genes can enter the population and be acted upon by evolution. E)The DNA replication process becomes more fine-tuned the more errors it makes.

D)New genes can enter the population and be acted upon by evolution.

How can two pea plants that have different genotypes for seed color be identical in phenotype? A)One of the two plants could be homozygous for the recessive allele while the other could be heterozygous. B)Genotype has no relation to phenotype. C)Seed color in pea plants is not genetically determined. D)One of the two plants could be homozygous for the dominant allele while the other could be heterozygous. E)One of the two plants could be homozygous for the dominant allele while the other could be homozygous for the recessive allele.

D)One of the two plants could be homozygous for the dominant allele while the other could be heterozygous.

Artificial selection is likely to produce population-level changes most quickly in organisms with: A)a small litter size. B)a long life span. C)a large body size. D)a short generation time. E)a large genome.

D)a short generation time.

Monogamy, a relatively rare system outside of birds, evolves when: A)females compete for males who have higher parental investment. B)males compete for females who have higher parental investment. C)both males and females have low parental investment. D)both males and females have high and equal parental investment. E)it is dangerous to compete for multiple mates.

D)both males and females have high and equal parental investment.

In the graph in the figure, the x axis represents _________________ and the y axis represents _________________. A)age class; number of mates B)number of offspring; fitness C)age class; number of offspring D)number of mates; number of offspring E)number of offspring; number of mates

D)number of mates; number of offspring

Evolution occurs: A)only when the environment is changing. B)only through natural selection. C)by altering physical traits but not behavioral traits. D)only via natural selection, genetic drift, migration, or mutation. E)almost entirely because of directional selection.

D)only via natural selection, genetic drift, migration, or mutation.

If a baby has "his father's nose," it's because: A)the baby has inherited the "father's nose" allele from his father. B)the baby has inherited the "father's nose" allele from his mother. C)the baby has not inherited the "suppress father's nose allele" from his mother. D)the baby has inherited many alleles from his father that work together to shape the baby's nose. E)the baby has been cobbled together from a bunch of used parts.

D)the baby has inherited many alleles from his father that work together to shape the baby's nose.

DNA is a macromolecule that stores information. Which component of DNA is the source of this information? A)the phosphate group B)the ladder C)the sugar D)the base E)the histone

D)the base

The process of using the information encoded in mRNA molecules to assemble polypeptides from amino acids is called: A)replication. B)the one gene-one enzyme hypothesis. C)the central dogma. D)translation. E)transcription.

D)translation.

In certain plants, red flowers are dominant to white flowers. If a heterozygous plant is crossed with a homozygous red-flowered plant, what is the probability that the offspring will be white-flowered? A)50% B)It depends on whether the traits are linked. C)100% D)25% E)0%

E)0%

Most genetic diseases result from mutations that cause a gene to produce a non-functioning ______________, which in turn blocks the functioning of a metabolic pathway. A)tRNA B)Histone C)Codon D)Polysaccharide E)Enzyme

E)Enzyme

Human babies quickly and easily develop a fear of snakes, yet they don't easily develop a fear of guns. Why? A)During most of the history of human evolution, snakes were dangerous to humans and guns didn't exist. B)Guns produce an "honest signal," while snakes do not. C)Guns are less dangerous than snakes. D)In order to learn fear of guns, human babies need to be exposed to another human expressing fear of guns, and this rarely happens. E)Fear of snakes is a fixed action pattern in humans.

E)Fear of snakes is a fixed action pattern in humans.

The fact that fish, penguins, and dolphins all have the same basic shape is BEST explained by which of the following? A)Parallel evolution is common among aquatic mammals. B)The similarities are probably due to random chance. C)Divergent evolution and adaptive radiation into new niches often result in convergent evolution. D)Fish, penguins, and dolphins all faced the same physical constraints during their evolution and converged upon the same body plan. E)The basic shapes of fish, penguins, and dolphins are vestigial structures.

E)The basic shapes of fish, penguins, and dolphins are vestigial structures.

In any DNA molecule, the number of guanine bases is: A)always equal to the number of adenine bases. B)sometimes equal to the number of thymine bases and sometimes equal to the number of adenine bases. C)always equal to the number of thymine bases. D)equal to the total number of cytosine and adenine bases. E)always equal to the number of cytosine bases.

E)always equal to the number of cytosine bases.

The division of the cytoplasm during cell division is referred to as: A)cytodivision. B)hybridization. C)cytoplasm splicing. D)vegetative growth. E)cytokinesis.

E)cytokinesis.

Mitosis results in: A)gametes. B)daughter cells with twice as much genetic material and a unique collection of alleles. C)daughter cells with the same number of chromosomes but different combinations of alleles. D)eight daughter cells. E)daughter cells with the same number and composition of chromosomes.

E)daughter cells with the same number and composition of chromosomes.

A storm washed 5 female and 5 male tiger beetles from the mainland to a small island that had no previous population of tiger beetles. In tiger beetles, having six spots (A) is dominant to having four spots (a). All 10 beetles had six spots, but 1 male and 1 female were heterozygous for the four-spot trait. If 6 of the beetles died randomly without reproducing, the ratio of the genotypes could be quite different in subsequent generations. This change in allele frequencies would be an example of: A)convergent evolution. B)natural selection leading to perfect organisms. C)mutation. D)stabilizing selection. E)genetic drift.

E)genetic drift.

When crossing over occurs, _______________ genes usually stay together. A)sex-linked B)multi-allelic C)pleiotropic D)independently assorting E)linked

E)linked

Cancer cells are different from other cells in that they have lost their "contact inhibition." "Contact inhibition" means: A)most cells don't begin to divide until they bump up against other cells or collections of cells. B)DNA replication in most cells doesn't begin until the double helix comes in contact with particular enzymes. C)DNA replication in most cells stops when the double helix comes in contact with particular enzymes. D)most cells stop dividing when they have reached 50 cell divisions. E)most cells stop dividing when they bump up against other cells or collections of cells.

E)most cells stop dividing when they bump up against other cells or collections of cells.

Many mosquito populations today are resistant to pesticides that were historically effective. This pesticide resistance arose in these populations because: A)these populations were outside the range of the original pesticide application. B)populations had to develop tolerance in order to survive. C)individual mosquitoes built up immunity to the pesticides after exposure. D)the pesticides caused mutations in the DNA of mosquitoes that conferred resistance phenotypes, and were passed on to subsequent generations. E)some individuals were resistant to the pesticides before they were used, and those mosquitoes were more likely to survive and reproduce.

E)some individuals were resistant to the pesticides before they were used, and those mosquitoes were more likely to survive and reproduce.

"Survival of the fittest" may be a misleading phrase to describe the process of evolution by natural selection because: A)it is impossible to determine the fittest individuals in nature. B)reproductive success on its own does not necessarily guarantee evolution. C)natural variation in a population is generally too great to be influenced by differential survival. D)fitness has little to do with natural selection. E)survival matters less to natural selection than reproductive success does.

E)survival matters less to natural selection than reproductive success does.

Transgenic bacteria are bacteria: A)that produce genes used in recombinant DNA technology. B)that have hybridized with other species of bacteria. C)found in the DNA of other organisms. D)that only have trans-DNA. E)that have a sequence of DNA from another organism inserted into them.

E)that have a sequence of DNA from another organism inserted into them.

A cross between homozygous red-eyed flies and homozygous white-eyed flies results in progeny that all have red eyes. This result demonstrates: A)the norm of reaction. B)dominance. C)the blending model of genetics. D)a dihybrid cross. E)the law of independent assortment.

E)the law of independent assortment.