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Collecting data based on observation is an example of __________; analyzing this data to reach a conclusion is an example of __________ reasoning

discovery science; inductive

Which of the following best describes an emergent property?

the whole is different than the sum of its parts

The correct sequence of biological classification from most inclusive to least inclusive is:

domain, kingdom, phylum, class, order, family, genus, species

When blood glucose level rises, the pancreas secretes insulin, and as a result blood glucose level declines. When blood glucose level is low, the pancreas secretes glucagon, and as a result blood glucose level rises. Such regulation of blood glucose level is the result of

negative feedback

Which branch of biology is concerned with the naming and classifying of organisms?


Two species that belong to the same genus must also belong to the same

all of the above

All of the following statements are part of Charles Darwin's concept of natural selection except

Characteristics of organisms are inherited as genes on chromosomes

Which of the following is (are) true of natural selection?

A, B, and C

Which of these individuals is most likely to be successful in an evolutionary sense?

an organism that dies after 5 days of life but leaves 10 offspring, all of whom survive to reproduce

T or F. Science requires that hypothesis be testable and falsifiable and that observations be repeatable


If a hypothesis is supported by considerable data, then

the hypothesis might be accepted as theory

Which of the following statements about evolution is true?

evolution is a genetic change in a population over time

Which statement about natural selection is most correct?

Well-adapted individuals leave more offspring, and thus contribute more to the next generation's gene pool, than do poorly adapted individuals

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?

A and C only

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are

B and C only

Which of these is the smallest unit upon which natural selection directly acts?

an individual's phenotype

Which of these is the smallest unit that natural selection can change?

a population's gene frequency

The process of evolution is not a purposeful progression


When we say that an individual organism has a greater fitness than another individual, we specifically mean that the organism

leaves more viable offspring than others of its species

Which describes brightly colored peacocks mating more frequently than drab peacocks?

sexual selection

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?

stabilizing selection

Which of the following is a properly written binomial for the bluegill sunfish? (Note: the information in parentheses desscribes the preceding words)

Lepomis macrochirus (in italics)

Male satin bowerbirds adorn structures that they build, called "bowers," with parrot feathers, flowers, and other bizarre ornaments in order to attract females. Females inspect the bowers and, if suitably impressed, allow males to mate with them. The evolution of this male behavior is due to

sexual selection

A biologist discovers two populations of wolf spiders whose members appear identical. Members of one population are found in the leaf litter deep within the woods. Members of the other population are found in the grass at the edge of the woods. The biologist decides to designate the members of the two populations as two separate species. Which species concept is this biologist most closely utilizing?


You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been described. Your assignment 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?


Closely related orders may be grouped into a single


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 separate?

the postzygotic barrier called hybrid inviability

Reproductive isolation may cause new species to form. Which of the following is not an example of reproductive isolation?

a large dominant male wolf that prohibits other wolves in his pack to mate


can involve changes involving a single gene

Phylogenetic hypotheses (such as those represented by phylogenetic trees) are strongest when

they are supported by more than one kind of evidence, such as when fossil evidence corroborates molecular evidence

Which of these taxa contains species that produce potent toxins that can cause extensive fish kills, contaminate shellfish, and poison humans?


All of the following are characteristics of most animals, except


A snail-like, coiled, porous test (shell) of calcium carbonate is characteristic of which group?


Which of the following terms or structures is properly associated only with animals?

Hox genes

What do animals as diverse as corals and monkeys have in common?

presence of Hox genes

Arthropods invaded land about 100 million years before vertebrates did so. This most clearly implies that

arthropods have had more time to co-evolve with land plants than have vertebrates

Cephalization is most closely associated with which of the following?

concentration of sensory structures at the anterior end

The sexual cycle of Plasmodium (underlined) takes place in ____________, while the asexual cycle takes place in ____________________. What choices best fill in hte blanks?

mosquitoes, humans

What distinguishes a coelomate animal from a pseudocoelomate animal is that coelomates

have a body cavity completely lined by mesodermal tissue, whereas pseudocoelomates do not

An animal that swims rapidly in search of prey that it captures using visual senses concentrated at its anterior end is likely to be

bilaterally symmetrical and cephalized

Natural selection changes allele frequencies because some ________________ survive and reproduce more successfully than others


A taxon that includes all the descendents of an ancestor is called


Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that only animals derive their nutrition

by ingesting it

In the phylogenetic tree, a common ancestor for both species C and E could be at position number?


Darwin analogized the effects of evolution as the above-ground portion of a many-branched tree, with extant species being the tips of the twigs. The common ancestor of two species is most analogous to which anatomical tree part?

a node where two twigs diverge

Beetle pollinators of a particular plant are attracted to its flowers' bright orange color. The beetles not only pollinate the flowers, but they mate while inside of the flowers. A mutant version of the plant with red flowers becomes more common with the passage of time. A particular variant of the beetle prefers the red flowers to the orange flowers. Over time, these two beetle variants diverge from each other to such an extent that interbreeding is no longer possible. What kind of speciation has occurred in this example, and what has driven it?

sympatric speciation, habitat differentiation

A proficient engineer can easily design skeletal structures that are more functional than those currently found in the forelimbs of such diverse mammals as horses, whales, and bats. That the actual forelimbs of these mammals do not seem to be optimally arranged is because

natural selection is generally limited to modifying structures that were present in previous generations and in previous species

Which definition of evolution would have been most foreign to Charles Darwin during his lifetime?

change in gene frequency in gene pools

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that

humans and chimpanzees share a relatively recent common ancestor

Which of the following properties or processes do we associate with living things?

all of the above

You are trying to identify an organism. It is an animal, but it does not have nerve or muscle tissue. It is neither diploblastic nor triploblastic. It is probably a


Scyphozoans predominantly have a ______________ body form


What is characteristic of all ecdysozoans?

some kind of exoskeleton, or hard outer covering

Which of the following organisms are deuterostomes?

both C and D

A radially symmetrical animal that has two embryonic tissue layers probably belongs to which phylum?


Corals are most closely related to which group?

sea anemones

Generally, members of which flatworm class(es) are (is) nonparasitic?


What would be the most effective method of reducing the incidence of blood flukes in a human population?

Reduce the freshwater snail population

Which of the following correctly characterizes the phylum Rotifera?

parthenogenic reproduction

Which molluscan class includes members that undergo embryonic torsion?


Which molluscan class includes marine organisms whose shell consists of eight plates?


Of the annelid classes below, which have externally segmented bodies?

Hirudinea (leeches)

Some species of which of the following annelid classes release an anticoagulant that is of medical significance?

Hirudinea (leeches)

Humans most frequently acquire trichinosis by

eating undercooked pork

The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?


Among the invertebrate phyla, phylum Arthropoda is unique in possessing members that have


A terrestrial animal species is discovered with the following larval characteristics: exoskeleton, system of tubes for gas exchange, and modified segmentation. A knowledgeable zoologist should predict that its adults would also feature

an open circulatory system

The possession of two pairs of antennae is a characteristic of


Which of the following can have long, movable spines?

class Echinoidea (sea urchins and sand dollars)

A farm pond, usually dry during winter, has plenty of water and aquatic pond life during the summer. One summer, Sarah returns to the family farm from college. Observing the pond, she is fascinated by some six-legged organisms that can crawl about on submerged surfaces or, when disturbed, seemingly "jet" through the water. Watching further, she is able to conclude that the "mystery organisms" are ambush predators, and their prey includes everything from insects to small fish and tadpoles.If the pond organisms are larvae, rather than adults, Sarah should expect them to have all of the following structures, except

sex organs

In a tide pool, a student encounters an organism with a hard outer covering that contains much calcium carbonate, an open circulatory system, and gills. The organism could potentially be a crab, a shrimp, a barnacle, or a bivalve. Which structure below would allow for the most certain identification?

a mantle

Which of the following is a diploblastic phylum of aquatic predators?


An elementary school science teacher decided to liven up the classroom with a salt-water aquarium. Knowing that salt-water aquaria can be quite a hassle, the teacher proceeded stepwise. First, the teacher conditioned the water. Next, the teacher decided to stock the tank with various marine invertebrates, including a polychaete, a siliceous sponge, several bivalves, a shrimp, several sea anemones of different types, a colonial hydra, a few coral species, an ectoproct, a sea star, and several gastropod varieties. Lastly, some vertebrates-a parrotfish and a clownfish-were added. She arranged for daily feedings of copepods and feeder fish.The bivalves started to die one by one; only the undamaged shells remained. To keep the remaining bilvalves alive, the teacher would have had to remove the

sea star

Chordate pharyngeal slits appear to have functioned first as

suspension-feeding devices

Terry catches a ray-finned fish from the ocean and notices that, attached to its flank, there is an equally long, snakelike organism. The attached organism has no external segmentation, no scales, a round mouth surrounded by a sucker and two small eyes. Terry thinks it might be a marine leech, a hagfish, or a lamprey.
Which feature excludes it from possibly being a leech?

its lack of external segmentation

What is a distinctive feature of the chondrichthyans?

a mostly cartilaginous endoskeleton

While on an intersession course in tropical ecology, Kris pulls a large, snakelike organism from a burrow (the class was granted a collecting permit). The 1-m-long organism has smooth skin, which appears to be segmented. It has two tiny eyes that are hard to see because they seem to be covered by skin. Kris brings it back to the lab at the field station, where it is a source of puzzlement to the class. Kris says that it is a giant oligochaete worm; Shaun suggests it is a legless amphibian; Kelly proposes it belongs to a snake species that is purely fossorial (lives in a burrow).
Which characteristic should permit the class to conclude that it is probably not a snake?

the absence of scales on its surface

Which of these is not considered an amniote?


Why is the amniotic egg considered an important evolutionary breakthrough?

It allows incubation of eggs in a terrestrial environment

Differentiation of teeth is observed in


No urinary bladder, females with one ovary, no teeth


An advantage of asexual reproduction is that

asexual reproduction enables the population to rapidly colonize habitats that are favorable to that population

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 to their offspring

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

Like many other fishes, bluehead wrasses utilize harem mating as they reproduce sexually, but unlike most fish

large females morph into reproductively competent males

Chemical signals exchanged between potential reproductive partners are called


A pseudocoelomate organism

none of the above

Cnidocytes are stinging cells that contain _____________ that are used to subdue and capture prey. Fill in the blank above


Trematodes are characterized by all of the following except:


In frog embryos, the blastopore becomes the


Spider fangs are called


Which of the following describe the arthropod body plan?

A, B, and C

Nautilus are members of which Class?


Birds and mammals are distinct from other Vertebrates due to which characteristic that they share with each other?


Snail shells are secreted by the


Unlike eutherians, both monotremes and marsupials

have some embryonic development outside the mother's uterus

Which of the following are the only extant animals that descended directly from dinosaurs?


How are primates different from all other mammals?

opposable thumbs in many species

Which extant chordates are postulated to be most like the earliest chordates in appearance?


Which of the following is descriptive of protostomes?

spiral and determinate cleavage, blastopore becomes mouth

In the territorial behavior of the stickleback fish, the red belly of one male elicits attacks from another male by functioning as

a sign stimulus

What type of signal is brief and can work at night or among obstructions?


The benefits of territoriality include

Increased reproductive success

The round dance of the bee

Indicates that food is close to the hive

You turn on a light and observe cockroaches scurrying to dark hiding places. What have you observed?


In optimal foraging

An animal obtains food in the most efficient way

A type of bird similar to a chickadee learns to peck through the cardboard tops of milk bottles left on doorsteps and drink the cream from the top. What term best applies to this behavior?

operant conditioning

Male insects attempt to mate with orchids but eventually stop responding to them. What term best applies to this behavior?


Some dogs love attention, and Frodo the beagle learns that if he barks, he gets attention. Which of the following might you use to describe this behavior?

The dog's behavior is a result of operant conditioning

Which of the following statements about evolution of behavior is correct?

A and B only

Optimal foraging involves all of the following except

maximizing the population size of the forager

Fred and Joe, two unrelated, mature male gorillas, encounter one another. Fred is courting a female. Fred grunts as Joe comes near. As Joe continues to advance, Fred begins drumming (pounding his chest) and bares his teeth. Joe then rolls on the ground on his back, gets up, and quickly leaves. This behavioral pattern is repeated several times during the mating season. Choose the most specific behavior described by this example.

agonistic behavior

Which scientist devised a rule that predicts when natural selection should favor altruism?

William Hamilton

In Belding's ground squirrels, it is mostly the females that behave altruistically by sounding alarm calls. What is the likely reason for this distinction?

Females settle in the area in which they were born, so the calling females are warning kin

Which of the following statements about ecology is incorrect?

Ecology is a discipline that is independent from natural selection and evolutionary history

Landscape ecology is best described as the study of

the factors controlling the exchanges of energy, materials, and organisms among ecosystem patches

__________________ is the study of animal beahvior


Experts 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 under 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

The per capita growth rate of a population where dispersal is not a factor is expressed as

b - d

When r is positive, the population size is


Predation, disease, and competition are examples of ______________ factors


Long-term studies of Belding's ground squirrels show that immigrants move nearly 2 km from where they are born and make up 1 to 8% of the males and 0.7 to 6% of the females in other populations. On an evolutionary scale, why is this significant?

These immigrants provide a source of genetic diversity for the other populations

The three basic variables that make up the life history of an organism are

age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode

As N approaches K for a certain population, which of the following is predicted by the logistic equation?

The growth rate will approach zero

Which of the following describes having more than one reproductive episode during a lifetime?


"Complete competitors cannot coexist" is a statement of the principle of

Competitive exclusion

Competition with other species helps to determine an organism's

Realized niche

Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation?

competitive exclusion

The tendency for two similar species to differ from one another more markedly in areas where they occur together is known as

Character displacement

A complex of interconnected food chains in an ecosystem is called a(n)

Food web

Which of the following is an example of Batesian mimicry?

a non-venomous snake that looks like a venomous snake

Which of the following is an example of aposematic coloration?

stripes of a skunk

Most of the organelles in a neuron are located in the

cell body

The species richness of a community refers to the

number of different species

In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)

keystone species

Species richness increases

as we travel north from the South Pole

Subtraction of which of the following will convert gross primary productivity into net primary productivity?

the energy used by autotrophs in respiration

The amount of chemical energy in consumers' food that is converted to their own new biomass during a given time period is known as which of the following?

secondary production

A secondary consumer, such as a fox, receives what percent of the energy fixed by primary producers in a typical field ecosystem?


Most of the neurons in the human brain are


An extension of a neuron that transmits signals to other cells is a/an


Multicellular organisms must keep their cells awash in an "internal pond" because

cells need an aqueous medium for the exchange of nutrients, gases, and wastes

An example of a connective tissue is the


A membrane potential is

a difference in electrical charge across a plasma membrane

All skeletal muscle fibers are both

striated and voluntary

The type of muscle tissue associated with internal organs, other than the heart, is

smooth muscle

Muscles are joined to bones by


In the communication link between a motor neuron and a skeletal muscle

the motor neuron is considered the presynaptic cell and the skeletal muscle is the postsynaptic cell

Suppose you are studying the nitrogen cycling in a pond ecosystem over the course of a year. While you are collecting data, a flock of 100 Canada geese lands and spends the night during a fall migration. What could you do to eliminate error in your study as a result of this event?

Find out how much nitrogen is consumed and eliminated by a Canada goose over about a 12-hour period and multiply this number by 100; enter this +/-value into the nitrogen budget of the ecosystem

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