The type of learning that causes specially trained dogs to salivate when they hear bells is called
you are interesdted in studying howorganisms react to a gradient of a variety of abiotic conditions and how they coexist in this gradient. The best location to conduct such a stdy is
an intertidal zone
In which of the following terrestrial biome pairs are both dependent upon peiodic burning?
chapparal and savanna
A female cat in heat urinates more often and in many places. Male cats congragate near the urine dposits and fight one another. Which of the following would be the ultimate cause of the male cat's response to the female's urinating behavior?
Male cats respond to the odor because it is a means of locating females in heat.
The benthic zone in an aquatic biome
often supports communities of organisms that feed largely on detrius
A certain species of pine tree survives only in scatteredlocations at elevations above 2,800m in the western United States. To understand why the tree grows only in these specific places, an ecologist should
investigate the various biotic and abiotic factors that are unique to high altitude
f a meteor impact or volcanic eruption injected a lot of dust into the atmosphere and educed the sunlight reaching earth's surface by 70% for one year, all or the folowing marine communities would be greatly affected except
deep-sea vent communities
Which example below will most likely guarantee that two closely related species will persist only as distinct biological species?
Reproductive isolation from one another
When we say that an individual organism has a greaer fitness than another individual, we specifically mean that organism
leaves more viable offspring than others of its species
In the territorial behavor of the stickleback fish, the red belly of one male elicits attack from one male from another male by functioning as a
Each of the following has a better chance of influencing gene frequencies in small populations than in large populations, but which one most consistently requires a small population as a precondition for its occurence?
Which of these five species in the evolutionary tree would likely have fossil records indicating that punctuated equilibrium was n important part of their evolutionary history?
V and W
If "x" indicates the location of fossils of two closely related species, then fossils of their most recent common ancestor are most likely to occur in which stratum?
Which pair would have been likely to agree that strata such as those depictedhere were deposited gradually over long periods of time by subtle mechanisms that are still at work?
Hutton and Lyell
Which of the following environmental features might influence microclimates?
all of the above (fallen log, soft drink can, tree, stone)
You are maintaining a small fruit fly population. After several generations, you notive that the viability of the fruit flies is decreased. The best way to reverse the trend is to
cross your flies with those from another lab.
In one species of beetle, one subspecies favors red flowers while another favors white flowers. The mutant red flowers become more common over time. Eventually, the two species are no longer able to interbreed. What type of speciation has occured?
sympatric speciation, habitat differentiation
Which describes brightly colored peacocks mating more frequently than drab peacocks?
Catastrohism, meaning th regular occurence of geological or meteorilogical disturbances, was Cuvier's attemtp to explain the existence of
the fossil record.
Which of the following groups of scientists is closely related with ethology?
von Frisch, Lorenz, and Tinbergen
If global warming continues at its present rate, which biomes will likely take place of the coniferous forest?
Temperate Broadleaf and Grassland
Which of the following is responsible for the summer and winter stratification of deep temperate lakes?
water is densest at 4 degrees celsius
Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. What is the mechanism for keeping the two frog species seperate?
the postzygotic barrier called hybrid inviability
Animals tend to maximize their energy intake-to-expidenture ratios. What is this behavior called?
Which tpe of biome would most likely occur in a climate with mild, rainy winters and hot, dry summers?
a biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of competition for food and predation. In a single generation, 90% of the squirrels that were born lived to reproduce, and the population increased to 80. Which inferences about this population might be true?
A, B, and C
Deserts that typically occur in a band at 30 degrees north and south latitude because
descending air masses tend to be cool and dry.
a Hardy-Weinberg population witii two alleles, A and a, that are in equilibrium, the frequency of the allele a is 0.4. What is the percentage of the population that is homozygous for this allele?
In mountainous areas of western North America, north-facing slopes would be expected to
support biological communities similar to those found at higher elevations on similar south facing slopes
Most Swiss starlings produce four to five eggs in each clutch. Those producing fewer or more than this have reduced fitness. Which of the following terms best describes this?
The theory of evolution is most accurately described as
an overarching explanation, supported by much evidence, for how populations change over time
in deer ecology generally agree that population sizes of deer that live in temperate climates are limited by winter snow. The deer congregate in "yarding" areas imder evergreen trees because venturing out to feed in winter is energetically too expensive when snowfall depths accumulate to above 40 cm. Deer often stay yarded until the spring thaw. Snow depth over 40 inches for more than 60 days results in high mortality due to starvation. This observation best illustrates which of the following principles about factors that limit distribution of organisms?
Environmental factors are limiting not only in amount but also in longevity.
Generalized global air circulation and precipitation patterns are caused by
rising, warm, moist air masses cool and release precipitation as they rise and then at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.
) In order for speciation to occur, what is true? --
at least one gene, affecting at least one phenotypic trait, must change.
A stickleback fish will attack a fish model as long as the model has red coloring. What term best applies to this behavior? -
DNA polymerases of all cellular organisms have proofreading capability. This capability tends to reduce the introduction of --
genetic variation by mutations.
Which of the following statements best describes the difference in approach to studying the environment by early naturalists compared to present-day ecologists? --
Early naturalists employed a descriptive approach; present-day ecologists generate hypotheses, design experiments, and draw conclusions from their observations.
During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should one expect to result from natural selection? -
more small-beaked birds dying than larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals? -
As a young biologist, Charles Darwin had expected the living plants of temperate South America would resemble those of temperate Europe, but he was surprised to find that they more closely resembled the plants of tropical South America. The biological explanation for this observation is most properly associated with the field of -
As climate changes because of global warming, species' ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that—
have seeds that are easily dispersed by wind or animals.
You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been described. Your assigriment is to separate them into species. There is no accompanying information as to where or when they were collected. Which species concept will you have to use? -
You turn on a light and observe cockroaches scurrying to dark hiding places. What have you observed'?
Which of the following statements about the ocean pelagic biome is true?
Pelagic ocean photosynthetic activity is disproportionately low in relation to the size of the biome
Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north-south mountain ranges, such as the Sierra Nevada and the Cascades. Which statement best describes the changes that these air masses undergo? --
the warm, moist Pacific air rises and cools, releasing precipitation as it moves up the 'windward side of the range, and this cool, now dry air mass heats up as it descends on the leeward side of the range.
Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?—
Ecosystem, community, population, individual
Which of these naturalists synthesized a concept of natural selection independently of Darwin? --
You are working for the Environmental Protection Agency and researching the effect of a potentially toxic chemical in drinking water. There is no documented scientific evidence showing that the chemical is toxic, but many suspect it to be a health hazard. Using the precautionary principle, what would be a reasonable environmental policy? -
Set the acceptable levels of the chemical conservatively low, and keep them there unless future studies show that they can be safely raised.
Darwin's mechanism of natural selection required long time spans in order to modify species. From whom did Darwin get the concept of Earth's ancient age?
In peas, a gene controls flower color such that R = purple and r = white. In an isolated pea patch. There are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the value of q for this population? -
Which of the following represents an idea that Darwin learned from \he writings of Thomas Malthus? -
populations tend to increase at a faster rate than their food supply normally allows
Sow bugs become more active in dry areas and less active in humid areas. This is an example of -
A rapid method of speciation that has been important in the history of flowering plants is --
Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would best help distinguish between an explanation based on homology versus one based on convergent evolution?, --
The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical.
Turnover of water in temperate lakes during the fall is made possible by which of the following—
the density of water changes as seasonal temperatures change.
Which is a true statement concerning genetic variation?
It must be present in a population before natural selection can act upon the population
The average birth weight for human babies is about 3 kg. Which of the following terms best describes this? -
What probably explains why coastal and inland garter snakes react differently to banana slug prey? -
Ancestors of coastal snakes that could eat the abundant banana slugs had increased fitness. No such selection occurred inland, where banana slugs were absent.
Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms? --
What was the prevailing notion prior to the time of Lyell and Darwin?
Earth is a few thousand years old, and populations are unchanging.
Carson would most likely have endorsed which of the following statements? -
the greatest liberty humans have taken is with nature.
Which of the following statements about light in aquatic environments is correct?
Water selectively reflects and absorbs certain wavelengths of light.
The recessive allele that causes phenylketonuria (PKU) is harmful, except when an infant's diet lacks the amino acid, phenylalanine. What maintains the presence of this harmful allele in a population's gene pool? -
Which describes an African butterfly species that exists in two strikingly different color patterns?--
Two plant species live in the same biome but on different continents. Although the two species are not at all closely related, they may appear quite similar as a result of -
A chemical produced by an animal that serves as a communication to another animal of the same Species is called -
A type of learning that can occur only during a brief period of early life and results in a behavior that's difficult to modify through later experiences is called -
Mules are relatively long-lived and hardy organisms that cannot, generally speaking, perform successful meiosis. Consequently, which statement about mules is true? -
They have a relative evolutionary fitness of zero.
Imagine some cosmic catastrophe jolts Earth so that its axis is perpendicular to the orbital plane between Earth and the sun. The most obvious effect of this change would be --|
the elimination of seasonal variation
Species introduced to new geographic locations--
can out-compete and displace native species for biotic and abiotic resources.
From earliest to latest, the overall sequence of early development proceeds as follows: --
cleavage, gastrulation, organogenesis
Hans Spemann and colleagues developed the concept of the primary organizer in amphibian embryos while studying the -
dorsal lip of the blastopore.
) Russian nesting dolls, which are a set of smaller dolls packed inside larger dolls, most resemble which of the following developmental theories?—
Animal development compares to plant development in that—
animal cells, but not plant cells, migrate during morphogenesis
In humans, identical twins are possible because
early blastomeres can form a complete embryo if isolated
A contraceptive pill that continuously inhibits the release of GnRH from the hypothalamus will
reduce the secretion of the gonadotropins from the anterior pituitary gland
. A cloaca is an anatomical structure found in many non-mammalian vertebrates, which functions as -
a common exit or the digestive, excretory, and reproductive systems
A temperature drop on the morning of day 14 in the menstrual cycle of the human female coincides with a peak in progesterone production by the uterus.—
the primitive streak in a bird is the functional equivalent of—
the lip of the blastopore in the frog
For water fleas of the genus Daphnia, switching from a pattern of asexual reproduction to sexual reproduction coincides with -
periods of temperature or food stresses
An advantage of asexual reproduction is that -
asexual reproduction enables the species to rapidly colonize habitats that are favorable to that species.
If you buy a pie that contains a swirled mixture of chocolate and vanilla filling. When you cut the pie up, you notice that some slices have more chocolate than vanilla and that other slices have more vanilla than chocolate. This uneven distribution of chocolate and vanilla is most like the uneven distribution of -
cytoplasmic determinants in a zygote
If the apical ectodermal ridge is surgically removed from an embryo, it will lose—
positional information for limb-bud pattern formation
Which statement is false concerning reproduction in invertebrate animals?-
None of the invertebrates have structures that store sperm
20 the primary function of the corpus luteum is to-
maintain progesterone and estrogen synthesis after ovulation has occurred
Genetic mutations in asexually reproducing organisms lead to more evolutionary change than do genetic mutations in sexually reproducing ones because-
asexually reproducing organisms, but not sexually reproducing organisms, pass all mutations y to their offspring
In vertebrate animals, spermatogenesis and oogenesis differ, in that-
Cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis.
The vegetal pole of the zygote differs from the animal pole in that -
the vegetal pole has a higher concentration of yolk.
In humans, the follicular cells that remain behind in the ovary following ovulation become -
steroid-hormone synthesizing structure called the corpus luteum
Cells move to new positions as an embryo establishes its three germ tissue layers during -
In close comparisons, external fertilization often yields more offspring than does internal fertilization, but internal fertilization offers the advantage that -
the smaller number of offspring produced often receive a greater amount of parental investment.
Sexual reproduction -
can produce diverse phenotypes that may enhance survival of a population in a changing environment
It is possible that in humans a chemical attractant associated with the egg or follicular fluid is responsible for selecting the relative small number of sperm that are physiologically ready to fertilize the egg. -
At the time of fertilization, the complete maturation of each oogonium has resulted in-
one secondary oocyte.
The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is -
ectoderm, mesoderm, endoderm.
Environmental cues that influence the timing of reproduction generally do so by -
direct effects on hormonal control mechanisms.
An embryo with meroblastic cleavage, extra-embryonic membranes, and a primitive streak must be that of -
Evidence that parthenogenic whiptail lizards are derived from sexually reproducing ancestors includes -
the requirement for male-like behaviors in some females before their partners will ovulate.
As cleavage continues during frog development, the size of the blastomeres -
decreases as the number of the blastomeres increases
If an amphibian zygote is manipulated so that the first cleavage plane fails to divide the gray crescent, then -
only the daughter cell with the gray crescent will develop normally
Sexual reproduction makes natural selection fore effective in yeast because it increases genetic variation. -
which of the following is true for both prokaryotic and eukaryotic gene expression? -
mRNA is synthesized in the 3' -> 5' direction.
of the promoter, called the TATA box, is said to be highly conserved in evolution. Which might this illustrate?-
any mutation in the sequence is selected against.
In the 1920s Muller discovered that X-rays caused mutation in Drosophila. In a related series of experiments, in the 1940s, Charlotte Auerbach discovered that chemicals—she used nitrogen mustards—have a similar effect. A new chemical food additive is developed by a cereal manufacturer. Why do we test for its ability to induce mutation? -
we want to prevent any increase in mutation frequency.
Which of the following statements are true about protein synthesis in prokaryotes? -
Translation can begin while transcription is still in progress.
What does the operon model attempt to explain? -
the coordinated control of gene expression in bacteria
10 A lack of this nonprotein molecule would result in the inability of the cell to "turn off" genes:
When this is taken up by the cell, it binds to the repressor so that the repressor no longer binds to the operator-
A mutation that inactivates the regulatory gene of a repressible operon in an E. coli cell would result in -
continuous transcription of the structural gene controlled by that regulator.
Transcription of the structural genes in an inducible operon -
starts when the pathway's substrate is present.
For a repressible operon to be transcribed, which of the following must occur? -
RNA polymerase must bind to the promoter, and the repressor must be inactive.
If glucose is available in the environment of £. Coli, the cell responds with very low concentration of cAMP. When the cAMP increases in concentration, it binds to CAP. Which of the following would you expect would then be a measurable effect? -
increased concentration of the trp enzymes
Muscle cells and nerve cells in one species of animal owe their differences in structure to -
moving different genes expressed
Which of the following mechanisms is (are) used to coordinately control the expression of multiple, related genes in eukaryotic cells?-
organization of the genes into clusters, with local chromatin structures influencing the expression of all the genes at once
Genomic imprinting, DNA methylation, and histone acetylation are all examples of -
In both eukaryotes and prokaryotes, gene expression is primarily regulated at the level of -
Gene expression might be altered at the level of post-transcriptional processing in eukaryotes rather than prokaryotes because of which of the following? -
eukaryotic exons may be spliced in alternative patterns.
21 Since Watson and Crick described DNA in 1953, which of the following might best explain why the function of small RNAs is still being explained? -
changes in technology as well as our ability to determine how much of the DNA is expressed nave now made this possible.
The fact that plants can be cloned from somatic cells demonstrates that -
differentiated cells retain all the genes of the zygote.
A cell that remains entirely flexible in its developmental possibilities is said to be -totipotent.
24 Which of the following serve as sources of developmental information? -
"Cytoplasmic determinants such as mRNAs and proteins produced before fertilization
Barbara McClintock, famous for discovering that genes could move within genomes, had her meticulous work ignored for nearly 4 decades, but eventually won the Nobel Prize. Why was her work so distrusted? -
Geneticists did not want to lose their cherished notions of DNA stability.
Charles Darwin was the first person to propose -
a mechanism for evolution that was supported by evidence.