Bio100 Final Exam – 34, 35, 36, & 37 (mastering questions)

The sum of all Earthʹs ecosystems is called the
A) troposphere.
B) stratosphere.
C) lithosphere.
D) hydrosphere.
E) biosphere.

E The biosphere is the global ecosystem: the sum of all the planet’s ecosystems, of all life and where it lives.

Which of these would be considered a biotic component of your environment?
A oxygen
B your friend
C water
D temperature

B your friend Living things compose the biotic portion of an environment.

An organism’s environment consists of _____.
A water for aquatic organisms and the atmosphere for terrestrial organisms
B nonliving factors such as temperature and chemicals
C other living organisms
D abiotic and biotic factors

D abiotic and biotic factors

A photograph of a Victorian trophy room shows the heads of 15 species of hoofed mammals, all shot within a day’s walk of a single hunting camp in Africa. This camp was probably located in
A savanna.
B tropical rain forest.
C chaparral.
D desert.

A savanna.

The kind of terrestrial biome that exists in a particular region depends largely on _____ and _____.
A soil … available nutrients
B sunlight … soil
C temperature … precipitation
D latitude … longitude

C temperature … precipitation

A desert rodent living in a biome created by the rain shadow of a mountain in Mexico would be expected to _____.

A be active primarily during the day
B be lightly colored, to blend into its environment and avoid predators
C live high off the ground, building a nest in the corner of branches of the trees
D have sharp teeth to slice through flesh

B be lightly colored, to blend into its environment and avoid predators Most desert rodents are prey to carnivores such as hawks. Camouflage is a great advantage.

When people speak of the "rain shadow" of the California Coast Range, they are referring to the

A shadow cast by the mist and clouds that hover above the crest of the range.
B scarcity of rain on the eastern flank and adjacent lowlands compared to the western flank.
C dark-colored chaparral vegetation that grows on the eastern flank.
D forested condition of the eastern flank of the range compared to the western flank.

B scarcity of rain on the eastern flank and adjacent lowlands compared to the western flank. On the leeward side of a mountain, cooler dry air descends, absorbing moisture and producing a rain shadow, an area of low precipitation.

If you travel from west to east through Ecuador, you will pass through tundra, taiga, temperate forest, and tropical forest. Which of the following climatic factors remains constant on such a trip?

A average rainfall
B maximum temperature
C day length
D soil type

C day length

What is the ultimate source of energy for nearly all surface terrestrial and shallow water ecosystems?
A sunlight
B wind
C water
D organic compounds

A sunlight

In the state of Washington, the prevailing winds blow eastward off of the ocean and up and over two mountain ranges. Biologists are searching for a rare fern plant that is known to prefer cool and wet environments, but hasn’t been seen in this state for many decades. Where would the biologists most likely find the plant?

A. on the west sides of the mountain ranges at lower elevations
B. on the east sides of the mountain ranges at lower elevations
C. on the west sides of the mountain ranges at higher elevations
D. on the east sides of the mountain ranges at higher elevations

C – on the west sides of the mountain ranges at higher elevations

The level of ecologic organization that incorporates abiotic factors is the
A) ecosystem.
B) symbioses
C) species.
D) population.
E) community

A

Which of the following statements about deserts and the organisms that live there is true?
A Desert plants typically produce very few seeds.
B Growth and reproduction occur year-round in deserts.
C Air temperatures in cold deserts, such as those west of the Rocky Mountains, may never fall below 30 degrees C.
D Many desert animals are nocturnal.

D Many desert animals are nocturnal.

A pronghorn can reach speeds of almost 100 km/hr. Ecologists believe that the pronghorn’s speed evolved _____.
A because 12,000 years ago the pronghorn’s major predator was the now-extinct American cheetah
B because pronghorns are hunted by wolves and coyotes
C as a very recent adaptation to changes in its habitat
D male pronghorns use their speed in competition with other males

A because 12,000 years ago the pronghorn’s major predator was the now-extinct American cheetah

The adaptations of pronghorns
A) to the open plains and shrub deserts of North America have helped them spread to nearly
every continent.
B) demonstrate that meeting the demands of local environmental conditions helps organisms
extend their ranges to other types of environments.
C) allow them to survive in forests, since they are herbivores.
D) include a reflective coat, an ability to find small pools of water, and chemical defenses against
most predators.
E) to open country could be a disadvantage in a densely forested environment.

E

Changes in the seasons are caused by
A) the tilt of Earthʹs axis toward or away from the sun
B) annual cycles of temperature and rainfall
C) variation inthe distance between Earth and the sun
D) anu annual cycle in the sunʹs energy output
E) the periodic build up of heat energy at the equator

A

In terms of global air circulation, the tropical regions are the regions where air
A) rises and warms, creating an arid belt.
B) descends and warms, dropping rain.
C) rises and cools, creating an arid belt.
D) rises and cools, dropping rain.
E) descends and warms, creating an arid belt.

D

Why are many of the world’s deserts located at latitudes of about 30° north and south?
A Earth is tilted on its axis.
B Warm air rises at about 30° north and south and spreads toward the poles and the equator.
C The greatest amount of solar energy per unit area is absorbed by Earth at about 30° north and south.
D Dry air, originating at the equator, descends toward Earth’s surface at about 30° north and south.

D Dry air, originating at the equator, descends toward Earth’s surface at about 30° north and south.

Most of the worldʹs deserts are located at latitudes where
A) hot, dry air moving toward the equator rises.
B) cold, dry air moving toward the equator descends.
C) cold, dry air moving toward the poles descends.
D) hot, dry air moving toward the poles rises.
E) hot, dry air moving toward the poles descends.

C

Species in widely separated biomes often appear display similar characteristics because of
A) mutations.
B) dominance.
C) coevolution.
D) evolutionary drift.
E) convergent evolution.

E

Which of the following statements about biomes, the major terrestrial ecosystems covering the
Earth, is true?
A) The different types of biomes are distinguished by wind and sunlight.
B) Each of the eight major biomes is restricted to just one or two continents.
C) Most biomes are characterized by a particular group of species.
D) Most natural biomes are unaffected by human activity.
E) Fire is very important in some biomes.

E

In contrast to tropical forests, temperate broadleaf forests _____.
A have a long growing season
B have a thick layer of leaf litter
C are less able to recover from disturbances such as logging
D are home to a greater diversity of trees

B have a thick layer of leaf litter Decomposition rates are slower in temperate broadleaf forests than they are in tropical forests.

Which of the following statements about tropical forests is true?

A. Tropical forests occur in equatorial regions with very long 16- to 20-hour days.
B. Once stripped, tropical rain forests regrow quickly, although with slightly less diversity.
C. The soils of tropical rain forests are typically rich in nutrients.
D. The forest structure consists of distinct layers that provide many different habitats.

D The forest structure consists of distinct layers that provide many different habitats.

The dominant herbivores in savannas are
A) worms.
B) gophers.
C) antelope.
D) giraffes.
E) insects.

E) insects.

Which of the following options correctly pairs a biome and its characteristics?
A) temperate grassland=cool to cold winters, wet summers
B) desert= dry, hot, no rainfall at all
C) chaparral=mild, rainy winters; long, hot, but wet summers
D) savanna=long, cold winters, vegetation dominated by conifers
E) tundra=very cold winters; only the upper layer of the soil thaws during summer

E) tundra=very cold winters; only the upper layer of the soil thaws during summer

Which of the following correctly lists the biomes in order from lowest precipitation (at the left) to highest precipitation (to the right)?
A desert, savanna, temperate grassland, tundra
B tundra, temperate broadleaf forest, desert, savanna
C savanna, coniferous forest, tundra, temperate broadleaf forest
D desert, tundra, temperate broadleaf forest, tropical rain forest

D desert, tundra, temperate broadleaf forest, tropical rain forest

What natural phenomenon maintains the presence of grasslands?
A heavy rains
B earthquakes
C permafrost
D periodic fires

D periodic fires Without periodic fires to keep growth in check, grasslands would give way to forests. Grasses recover from fires much more quickly than other plants because they grow from underground shoots rather than above-ground shoots.

Earth’s biosphere is not completely self-contained (or closed) because _____.
A plants, algae, and photosynthetic bacteria obtain energy from sunlight, and heat escapes from the biosphere into space
B the precipitation that falls on the interior of western North America is derived from the Pacific Ocean
C bacteria that live on snowy mountains receive nutrients blown to them by winds
D humans pollute the atmosphere and bodies of water

A plants, algae, and photosynthetic bacteria obtain energy from sunlight, and heat escapes from the biosphere into space Solar energy represents an input to the biosphere from outside, and heat escape represents a loss from the biosphere.

Which of the following biomes, dominated by cone-bearing evergreen trees, is the largest terrestrial biome?
A savanna
B tropical rain forest
C chaparral
D coniferous forest

D coniferous forest Coniferous forests contain cone-bearing evergreen trees and constitute the largest biome on Earth.

Huge herds of bisons and pronghorn antelopes once roamed the North American _____.
A taiga
B grasslands
C broadleaf forests
D desert

B grasslands Most of central North America was covered by temperate grassland, once home to large herds of bison.

What factor is responsible for the moderate winters that characterize the chaparral biome?
A low rainfall
B a high incidence of solar radiation
C high winds
D cool ocean currents

D cool ocean currents Offshore cool coastal currents usually result in mild, rainy winters and long, hot, dry summers.

Which of these is a population?
A all of the people living in your state
B you and all of the prokaryotes living in and on you
C you
D a tropical rain forest

A all of the people living in your state A population consists of all of the organisms of the same species found in a particular geographic area.

Which of the following is characteristic of the chaparral biome?
A dense, broadleaf shrubs
B low amounts of rainfall at unpredictable periods throughout the year
C many plants with seeds that need fire to germinate
D animal species limited to lizards and snakes

C many plants with seeds that need fire to germinate

"Mediterranean" is another name for this type of biome.
A chaparral
B temperate grasslands
C taiga
D desert

A The climate that gives rise to the chaparral biome is characterized by warm to hot, dry summers and mild to cool, wet winters.

Temperate broadleaf forests are characterized by _____.
A little precipitation, mostly in the form of snow
B a thick layer of permafrost
C a broad range of temperatures ranging from -30°C to 30°C
D hemlock, Douglas fir, and redwood trees

C a broad range of temperatures ranging from -30°C to 30°C Temperate broadleaf forests experience annual cycles of very cold to very hot temperatures.

In which of the following biomes would you expect to find the highest abundance of large, grazing
animals?
A) temperate forest
B) tropical rain forest
C) temperate grassland
D) chaparral
E) desert

C

A coniferous forest would be characterized by _____.
A shrubs
B grasses and a few scattered trees
C broadleaf trees
D cone-bearing evergreen trees

D cone-bearing evergreen trees A northern coniferous forest, or taiga, supports cone-bearing trees, such as pine, spruce, fir, and hemlock.

In which of the following biomes would you expect decomposers to work most rapidly and efficiently?
A taiga
B tundra
C savanna
D tropical rain forest

D tropical rain forest Tropical rain forest temperatures accommodate rapid rates of decomposition and thus quickly recycle nutrients from dead organisms back to living organisms.

What do savanna, chaparral, temperate grassland, and coniferous forest biomes have in common?
A They are maintained by grazing.
B They are characterized by gymnosperms.
C Periodic fires play a role in maintaining these ecosystems.
D They are dominated by grasses

C Periodic fires play a role in maintaining these ecosystems.

Of these terrestrial biomes, vertical stratification (layers of plants) is most pronounced in the _____.
A tundra
B grassland
C desert
D tropical rain forest

D tropical rain forest Tropical rain forests have pronounced vertical stratification, which provides varied habitats and abundant rainfall, both of which favor a great diversity of species.

Which of the following links all parts of the biosphere together?
A the water cycle
B the tides
C the doldrums
D transpiration

A the water cycle

Which of the following factors is fundamentally responsible for the character of arctic tundra soils?
A) high aluminum content due to a low rate of leaching
B) abundant winter snow
C) permafrost
D) summer aridity
E) secretion of acid by lichens and plant roots

C) permafrost

An owl and a hawk both eat mice. Which of these terms describes the relationship between a hawk
and an owl?
A) parasitism
B) competition
C) predation
D) mutualism
E) commensalism

B) competition

Which of the following is an example of predation?
A) mechanical devices, such as quills in a porcupine
B) a hawk swooping down quickly to capture, kill, and eat a prairie king snake
C) the vivid colors of the poison-arrow frog in Costa Rica
D) a goldfinch feeding on the seeds of a thistle plant
E) a lizardʹs camouflage

B) a hawk swooping down quickly to capture, kill, and eat a prairie king snake

In an ecosystem, you would expect to find interspecific competition between
A) two wasp species that mimic each otherʹs appearance.
B) males of a species during the breeding season.
C) males and females of a species in which both sexes occupy the same niche.
D) populations of two species that occupy the same niche.
E) a prey species and its predator.

D) populations of two species that occupy the same niche.

One mechanism that prey populations evolve to avoid predation is
A) increasing the number of offspring produced.
B) secretion of enzymes that break down toxic plant compounds.
C) secretion of digestive enzymes that hydrolyze glucose.
D) chemical defenses
E) development of a short gestation period.

D) chemical defenses

On Earth, most organic molecules are produced by
A) glycolysis.
B) photorespiration.
C) cellular respiration.
D) photosynthesis.
E) hydrolysis.

D) photosynthesis

The number of species in a community is called the
A) community.
B) species richness.
C) species diversity.
D) species index.
E) species population.

B) species richness

The sum total of a populationʹs use of the biotic and abiotic resources of its habitat constitutes its
A) environment.
B) distribution.
C) range.
D) evolution.
E) niche.

E) Niche

A series of reciprocal adaptations in two species defines
A) competitive exclusion.
B) niche compartmentalization.
C) interspecific competition.
D) coevolution.
E) resource partitioning.

D) coevolution Coevolution occurs when a change in one species acts as a new selective force on another species, and counteradaptation of the second species in turn affects the selection of individuals in the first species.

In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the
grasshoppers are
A) primary consumers.
B) primary producers.
C) secondary consumers.
D) detritivores.
E) secondary producers.

A) primary consumers

The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled
within the ecosystem itself.
A) organic compounds . . . minerals
B) minerals . . . energy compounds
C) food . . . energy
D) energy . . . chemicals
E) genetic information . . . genotypes

D) energy… chemicals

In a food chain consisting of phytoplankton → zooplankton → fish → fishermen, the fishermen are
A) primary producers.
B) primary consumers.
C) secondary consumers.
D) tertiary consumers.
E) secondary producers.

D) tertiary consumers

The primary decomposers of a community are called
A) protozoa.
B) detritivores.
C) primary consumers.
D) primary producers.
E) herbivores.

B) detritivores.

When a New England farm is abandoned, its formerly plowed fields first become weedy
meadows, then shrubby areas, and finally forest. This sequence of plant communities is an
example of
A) genetic drift.
B) evolution.
C) secondary succession.
D) a phylogenetic trend.
E) a trophic chain.

C) secondary succession

In an ecosystem, about how much of the energy in producers will be available to secondary
consumers in this ecosystem?
A) 100%
B) about 0.1%
C) 50%
D) about 10%
E) about 1%

E) about 1%

Which of the following substances is cycled between organic matter and abiotic reservoirs?
A) protein
B) nucleic acid
C) enzymes
D) carbon
E) fat

D) carbon

Given that CO2 is produced by respiration, why does the amount of CO2 in the atmosphere
remain relatively constant? (When answering this question, exclude the impact of human activities
on atmospheric CO2.)
A) CO2 is trapped in dead organismsʹ bodies.
B) CO2 is split apart during photosynthesis.
C) CO2 is converted in photosynthesis to carbohydrates.
D) CO2 is a buffer.
E) CO2 mostly forms carbonate rocks.

C) CO2 is converted in photosynthesis to carbohydrates.

Carbon mainly cycles between the biotic and abiotic worlds through the processes of
A) transpiration and photosynthesis.
B) respiration and photosynthesis.
C) evaporation and photosynthesis.
D) respiration and transpiration.
E) respiration and evaporation.

B) respiration and photosynthesis.

Answers to questions about the immediate mechanisms for a behavior are called

A. proximate causes.
B. ultimate causes.
C. cognitive mapping.
D. conclusions.

A. proximate causes.

The evolutionary explanations for behavior are called the
A selected advantage.
B evolutionary schematic.
C proximal causes.
D ultimate causes.

D ultimate causes.

When a nipple is placed in a newborn baby’s mouth, the infant will immediately begin to suckle. This is an example of
A classical conditioning.
B innate behavior.
C imprinted behavior.
D imitation.

B innate behavior.

You are driving down the road in your car and stop to pick up your friend. After a few minutes, she asks, "What is that rattling noise?" You listen closely and then realize it is the sound of golf balls you tossed into your trunk a week ago. You reply, "Oh, it’s some golf balls. I guess I tuned out that sound long ago!" Your "tuning out" of that sound is an example of _____.

A social learning
B associative learning
C habituation
D imprinting

C habituation

The modification of behavior based upon specific experiences defines
A conditioning.
B imprinting.
C habituation.
D learning.

D learning.

Just as her eggs start hatching, a mother goose is killed by a fox. A farmer watches the unfortunate event and brings the eggs back to the farm to keep them warm. As they hatch, the farmer feeds the goslings until they can roam free. One day, someone saw the goslings following the farmer and remarked, "Boy, those geese sure do love you!" The farmer replied, "Oh, not exactly, you see, it is really a case of _____."
A associative learning
B habituation
C imprinting
D problem solving

C imprinting Imprinting is the irreversible and limited learning that occurs during a sensitive period in an animal’s life. The geese simply imprinted on the farmer.

Whooping cranes raised by sandhill cranes were accepted, raised, and taught to migrate by their surrogate sandhill crane parents. When they matured, the whooping cranes showed no interest in breeding with other whooping cranes. This unfortunate desire to mate with sandhill cranes was a fine example of whooping cranes showing _____.
A imprinting
B cognitive mapping
C associative learning
D habituation

A imprinting Imprinting is the irreversible and limited learning that occurs during a sensitive period in an animal’s life. The whooping cranes simply imprinted on the sandhill cranes.

A male turkey that imprinted onto a human at hatching is transferred as an older juvenile to a flock of "normal" turkeys. When this turkey reaches sexual maturity, he will probably try to court
A male, female, or immature turkeys indiscriminately.
B mature female turkeys.
C humans.
D immature male turkeys.

C humans.

Jacob noticed that a crow in his backyard seemed to be searching under the lawn chairs for something. The crow would toss the leaves and search only under the chairs. Later Jacob learned that his brothers had been eating popcorn outside and that they dropped popcorn under the chairs. Jacob went outside to look under the chairs and could not see any popcorn left. But just out of curiosity, he moved the set of chairs about 20 feet to the back of the yard. Then he watched. What looked like the same crow came back to the yard and searched for food under the chairs that had been moved, and not where the popcorn had been spilled. In this particular situation, it appears that the crow was exhibiting _____.
A imprinting
B spatial learning
C habituation
D associative learning

B spatial learning Spatial learning occurs when an organism uses landmarks to understand the spatial structure of the environment.

After many hours of observation, Jennifer noticed that a squirrel in her backyard seemed to retreat up a certain tree every time it was frightened. At the base of that tree was a wheelbarrow. Jennifer wondered how the squirrel found the same tree each time. Perhaps it simply knew to use the tree with the wheelbarrow. That night, Jennifer moved the wheelbarrow a few feet over and placed it against another tree. The next day, the squirrel retreated up the new tree, with the wheelbarrow resting at its base. This experiment suggests that the squirrel was using
A habituation.
B social learning.
C spatial learning.
D imprinting.

C spatial learning.

A blue jay hides hundreds of nuts throughout the fall and finds them throughout the winter and spring. The blue jay is most likely finding the stored food by using
A social learning.
B imprinting.
C kinesis.
D a cognitive map.

D a cognitive map.

The most extensive study of cognitive maps has involved animals that
A burrow extensive tunnels into the ground.
B migrate.
C build nests.
D hibernate.

B migrate.

Squirrels on a bird feeder seem to be able to figure out how to steal seeds no matter what people do to prevent it. Yesterday, Jeremy hung out a new bird feeder design, and sure enough, by the end of the day the squirrels found a way to get to the seeds. The squirrels most likely figured out how to get the seeds through
A trial-and-error learning.
B the use of cognitive maps.
C spatial learning.
D imprinting.

A trial-and-error learning.

In England, at a time when milk was still delivered to doorsteps each morning in foil-capped glass bottles, a songbird called the great tit started pecking through the caps and drinking the cream in the necks of the bottles. This behavior spread through the great tit population in a matter of years. The emergence and spread of this behavior probably depended on
A trial and error learning plus social learning.
B trial and error learning plus imprinting.
C trial and error learning plus habituation.
D habituation plus social learning.

A trial and error learning plus social learning.

The baby bobcats watched as their mother stalked a rabbit and pounced, catching a meal that was shared by all. The next day, two of the young bobcats were seen stalking a field mouse, which quickly escaped from the inexperienced hunters. The young bobcats were learning how to hunt by the process of
A social learning.
B associative learning.
C imprinting.
D habituation.

A social learning.

A big difference between social learning and imprinting is that
A imprinting does not involve a reward.
B imprinting can only take place among members of the same species.
C social learning is not limited to a sensitive period.
D social learning has a primarily genetic basis.

C social learning is not limited to a sensitive period.

A hawk soars widely over its range, searching for a meal. The mice below are abundant, but the hawk is large and the mice are small. More nutritious, but more difficult to find, are rabbits. On average, rabbits weigh about 75 times more than mice. Based on optimal foraging strategy, we would predict that if a hawk can catch a mouse every 10 minutes, it would be willing to search for one rabbit for up to _____.

A. 12 hours
B. 5 hours
C. 2 hours
D. an hour

A. 12 hours Optimal foraging strategy is a feeding behavior that provides maximal energy gain with minimal energy input. Using these figures, a hawk eating a rabbit every 12.5 hours would gain as much energy as eating one mouse every 10 minutes. Catching a rabbit in less than 12.5 hours would be more efficient.

An insectivorous bird has the choice of eating (1) meadow beetles, which are abundant and large but expose the bird to hawk predation; (2) under-a-rock beetles, which are large and fatty but hard to obtain; and (3) under-a-leaf beetles, which are easy to obtain but small. The bird has nestlings to feed. As an optimal forager, it will

A concentrate on under-a-leaf beetles because they are easy and safe.
B eat all three kinds of beetles, balancing the energy spent and the risks incurred against the energy gained.
C eat one kind of beetle at a time (first under-a-leaf, then meadow, then under-a-rock), switching to a new kind when the old kind becomes scarce.
D concentrate on under-a-rock beetles because they are energy-rich.

B eat all three kinds of beetles, balancing the energy spent and the risks incurred against the energy gained.

Organisms communicate in ways that are most suitable to their environments. Which of the following forms of communication would be most surprising if true?
A a brightly colored bat using its coloration to attract a mate during the middle of the night
B ants using a pheromone to mark a trail leading to food in the morning
C a chimp grooming a higher-ranking chimp for appeasement during midafternoon
D a woodpecker singing a song to attract a mate in a dark forest in early evening

A a brightly colored bat using its coloration to attract a mate during the middle of the night

Based on von Frisch’s work on honeybee communication, which of the following types of information will be communicated to other workers by a honeybee’s "dance"?
A the quality of the nectar
B the direction of the nectar source
C the distance of the nectar source from the nearest water
D the color of the flowers producing the nectar

B the direction of the nectar source

During the spring, male sage grouse gather in an open area and strut about, erecting their feathers in a fanlike display. They also make booming sounds using their inflated air sacs. The function of this dance is to
A attract the attention of females.
B select the showiest females and mate.
C frighten off smaller birds from the territory.
D imprint the younger male birds.

A attract the attention of females.

Which of the following mating systems would most likely be monogamous?

A Both parents are promiscuous, and both parents are needed to raise the offspring.
B The male guards the female closely, and both parents are needed to raise the offspring.
C Both parents are promiscuous, and only one parent is needed to raise the offspring.
D The female is promiscuous, and both parents are needed to raise the offspring.

B The male guards the female closely, and both parents are needed to raise the offspring. Monogamy is most likely to occur when there is increased confidence in paternity and when both parents are needed to provide for the offspring.

The need for intense parental care of offspring favors mating systems that are
A monogamous.
B lifelong.
C promiscuous.
D polygamous.

A monogamous.

Two male bighorn sheep butt heads to determine who gets the right to breed with a local group of females; a pack of wolves coordinate their strategy to attack a struggling newborn elk; a male peacock displays his feathers to entice a nearby hen to mate; and a school of tuna scatters and then reforms as a shark dashes quickly among them. All of these interactions represent _____.

A defense of a territory
B courtship displays
C agonistic behavior
D social behavior

D social behavior

Which of the following terms broadly describes any kind of interaction between two or more animals?

A foraging behavior
B dominance hierarchy
C competition
D social behavior

D social behavior

Territories are typically used for activities such as

A identification of kin and rearing young.
B feeding and identification of kin.
C feeding, mating, and rearing young.
D migration and feeding.

C feeding, mating, and rearing young.

Which of the following situations represents an example of territorial behavior?

A Digger wasps are able to recognize the pattern of landmarks around their nests.
B Troops of monkey species use well-defined, widely overlapping ranges. Troops avoid encountering each other and are aggressive if they meet.
C Gannets breed in dense colonies. Each gannet defends the area within the beak’s reach of its nest, but gannets feeding at sea are indifferent to each other.
D Sow bugs become more active and move around randomly if they find themselves in a dry area.

C Gannets breed in dense colonies. Each gannet defends the area within the beak’s reach of its nest, but gannets feeding at sea are indifferent to each other.

In early spring in western Kentucky, as is true for most parts of the United States, one of the most abundant bird species starts its mating season. Male red-winged blackbirds arrive first to the wetlands and quickly begin to define a place to meet their mate. Any nearby male will quickly be confronted, with the dominant bird claiming the space. As time goes on, males define their own spaces, where they typically mate with three to six females. The behavior of these male red-winged blackbirds best represents _____.
A kin selection
B reciprocal altruism
C agonistic behavior in the defense of a territory
D altruistic behavior

C agonistic behavior in the defense of a territory

Bighorn sheep are commonly found in portions of the Rocky Mountains and other parts of the western United States and Canada. Male bighorn sheep, called rams, use their large curled horns in dramatic head-butting rituals that help to determine who is the dominant ram. The dominant ram is more likely to breed with the females in that territory. Amazingly, these rituals usually end with minimal damage to both animals. Resolving conflicts with minimal harm is characteristic of _____.

A altruistic behavior
B reciprocal altruism
C agonistic behavior
D kin selection

C agonistic behavior Agonistic behaviors include threats, tests of strength, or combat to settle disputes while minimizing harm to both parties.

Which of the following would be an example of agonistic behavior?

A Ants mark their trails by releasing pheromones.
B A dog raises its hackles, bares its teeth, and stands high to appear threatening.
C A honeybee does a waggle dance to indicate the direction of food.
D A male ruffed grouse spreads its tail and beats its wings to attract a female.

B A dog raises its hackles, bares its teeth, and stands high to appear threatening.

Agonistic behavior
A is rare among vertebrates.
B increases the number of individuals who mate.
C is typically used to determine access to food, mates, or territories.
D usually causes serious injury to one or both of the combatants.

C is typically used to determine access to food, mates, or territories.

From a sociobiological perspective, altruism is a behavior that
A has the potential to enhance the altruist’s fitness at a later point in time.
B occurs only in the social insects.
C will always be selected against.
D does not have a genetic basis.

A has the potential to enhance the altruist’s fitness at a later point in time.

My dog gets very excited when he sees a dog cookie. Thus, the cookie is _____.
A a reward
B the ultimate cause of the behavior
C the proximate cause of the behavior
D a sign stimulus

C the proximate cause of the behavior

What type of behavior is performed the same way by all members of a species?
A learning
B cognition
C trial-and-error learning
D innate behavior

D innate behavior Innate behavior is behavior that is performed virtually the same way by all members of a species.

Ants carry dead ants out of an anthill and dump them on a trash pile. If a live ant is painted with a chemical from dead ants, other ants repeatedly carry it, kicking and struggling, to the trash pile, until the substance wears off. Which of the following explains this behavior?
A The ants have become imprinted on the chemical.
B The chemical triggers a negative taxis.
C The chemical is a sign stimulus for a fixed action pattern.
D The ants continue the behavior until they become habituated.

C The chemical is a sign stimulus for a fixed action pattern. The chemical is a trigger for a stereotyped behavior that is rarely interrupted once it has begun.

Operation Migration is a program that teaches young whooping cranes to migrate. This is an example of _____.
A cognitive mapping
B imprinting
C habituation
D associative learning

B imprinting

Trout automatically orient themselves to swim upstream; such a behavior is an example of _____.
A kinesis
B positive taxis
C negative chemotaxis
D positive phototaxis

B positive taxis The trout are orienting themselves to face into the current.

The movement of monarch butterflies from coastal California to central Mexico and back again is an example of _____.
A migration
B circadian rhythms
C positive taxis
D kinesis

A migration Migration is regular movement between two geographic points.

You are told that the song of males among a particular songbird species has an innate component but is also largely learned. Nestling males imprint on their father’s song and then sing it themselves when they reach sexual maturity. Which of the following observations would lead you to doubt this information?

A A male chick who is reared in isolation but hears tape recordings of his species’ song grows up to sing normally.
B A male chick reared in isolation but introduced as an older juvenile into an aviary containing normal males of his species sings his species’ song.
C A male chick who is reared in isolation but hears tape recordings of a different species’ song grows up to sing that species’ song.
D A male chick fostered in the nest of a different species grows up to sing the song of its foster species.

B A male chick reared in isolation but introduced as an older juvenile into an aviary containing normal males of his species sings his species’ song.

A group of individuals of a single species that occupy the same general area defines a
A subspecies.
B community.
C clone.
D population.

D population.

Which of the following situations would most likely lead to a uniform distribution of organisms?

A the distribution of dung beetles that feed on freshly deposited dung in a cattle pasture
B the distribution of male beta fish defending their territories
C the distribution of wolves in Yellowstone National Park
D the distribution of rooted, aquatic plants that grow to a height of about 1 meter in a large, deep pond

B the distribution of male beta fish defending their territories Territorial behavior often results in an even distribution of organisms as each animal defends a range.

Assume that there are five alligators per acre in a swamp in northern Florida. This is a measure of the alligator population’s
A density.
B range.
C dispersion.
D intrinsic rate of increase.

A density.

The pattern of distribution for a certain species of kelp is clumped. We would expect that the pattern of distribution for a population of snails that live on the kelp would be
A random.
B uniform.
C homogeneous.
D clumped.

D clumped.

You drive through Iowa in the spring and notice that along a stretch of several kilometers, every third fence post has a male redwing blackbird perched on it defending its nesting territory. This is an example of
A random dispersion.
B artificial dispersion.
C uniform dispersion.
D clumped dispersion.

C uniform dispersion.

The density of Douglas firs in an old-growth forest is estimated by counting the Douglas firs in four sample plots of 1 hectare each. The number of fir trees in the plots is 10, 12, 7, and 11, respectively. What is the estimated density of firs in the forest?
A 10 trees per hectare
B 25 trees per hectare
C 20 trees per hectare
D 5 trees per hectare

A 10 trees per hectare

To obtain optimal production in a small garden, one should
A. plant seeds in rows with minimal spacing between rows.
B. plant seeds in a uniform pattern throughout the garden.
C. plant seeds in clumps with large spaces between clumps.
D. sow seeds randomly throughout the garden.

B. plant seeds in a uniform pattern throughout the garden.

A bluegill population is at its carrying capacity in a stable lake in Minnesota. Biologists studying the bluegills’ reproductive behavior learn that a single female in one breeding season can produce 1,000 to 70,000 eggs. We can expect that the life table of these Minnesota bluegills will indicate _____.

A. little mortality in the early and middle stages of life but great mortality once sexual maturity is achieved
B. an initially low mortality followed by a steep increase in mortality through the middle and final stages of the life span
C. high early mortality in a Type III survivorship curve
D. a steady and even decline in the number of survivors throughout the life span

C. high early mortality in a Type III survivorship curve The production of very high numbers of offspring typically indicates extremely high mortality of the youngest members of a species.

A survivorship curve is a…
A. graph that shows the effect of predation on a prey population.
B. graph that plots an individual’s likelihood of reproducing as a function of age.
C. model for population growth that incorporates the concept of carrying capacity.
D. graph that plots an individual’s likelihood of being alive as a function of age.

D. graph that plots an individual’s likelihood of being alive as a function of age.

A Type I survivorship curve is associated with which of the following life history traits?
A large numbers of offspring being produced
B a short life span for most individuals
C parents providing extended care for their young
D infant mortality being much greater than adult mortality

C parents providing extended care for their young

A survivorship curve that involves producing very few offspring, each of which has a high probability of surviving to adulthood, is typical of
A rodents.
B oysters.
C sea stars.
D elephants.

D elephants.

A small population of 1,000 mice lives on a 100-acre island in the middle of a large lake. One dry summer, the lake level drops dramatically. The island’s size increases to 1,000 acres, and the island remains at this expanded size. The vegetation quickly spreads, and the mouse population grows. The population expands greatly, doubling in size each year for three straight years. However, the hawk populations expand too. From the fourth year until the present, the death rate of the mouse population has been equal to the birth rate. Which of the following statements about this population of mice is true?

A The current mouse population is much less than the carrying capacity.
B The new population is about 16,000 mice.
C The logistic curve for this population will be J-shaped.
D The population density of the mice went from 10 mice per acre before the lake level changed to 8 mice per acre at its new carrying capacity.

D The population density of the mice went from 10 mice per acre before the lake level changed to 8 mice per acre at its new carrying capacity.

The maximum number of individuals a habitat can support is called its
A community size.
B reproductive potential.
C carrying capacity.
D density-dependent factor.

C carrying capacity.

Consider a stable frog population living at carrying capacity in a pond. If an average female produces 6,000 eggs during her lifetime and an average of 300 tadpoles hatch from these eggs, how many of these tadpoles will, on average, survive to reproduce?
A more than 100
B 10 to 20
C 2
D 0

C 2

Which of the following is the best example of an abiotic factor limiting population size?
A the amount of aquatic plants eaten by snails in a pond
B the number of dead standing trees available as nesting sites for downy woodpeckers
C the spread of deadly human flu virus from one person to another by touching and sneezing
D the frequency of rainfall needed for the germination of desert plant seeds

D the frequency of rainfall needed for the germination of desert plant seeds

A tidal wave wipes out the entire population of mice living on an island. This is an example of
A a density-dependent effect.
B the interaction between density-dependent and abiotic factors.
C the effects of abiotic factors.
D Type III survivorship.

C the effects of abiotic factors.

In the logistic growth model, as population size increases, birth rates
A decline and/or death rates increase.
B and death rates increase.
C decline but death rates remain steady.
D remain constant and death rates increase.

A decline and/or death rates increase.

Which of the following is most clearly a case of density-dependent population regulation?
A the first hard frost of fall for a population of annual morning glory vines
B the occurrence of rainstorms for an opportunistic desert annual
C a dangerous new flu strain that is transmitted among humans by sneezing
D the summer drying of savanna grass for an insect that feeds on grass sap

C a dangerous new flu strain that is transmitted among humans by sneezing

An ecologist hypothesizes that predation by a particular owl species is the major factor controlling the population of a particular rabbit species. The first step in testing this hypothesis would be to determine
A whether populations of the rabbit that live outside the range of the owl have higher population densities.
B whether the owls eat the rabbits.
C what food the rabbits eat.
D to which diseases the rabbit population is subject.

B whether the owls eat the rabbits.

Which of the following would likely decrease the Earth’s human carrying capacity?
A improving agricultural technology to increase sustainable crop yields
B reducing fossil fuel consumption
C delaying the age of first reproduction
D increasing meat production

D increasing meat production Using more plants to produce more meat would decrease the amount of calories available to humanity. Meat production is a much less efficient process.

Biologists often determine population density by capturing animals and marking them for later identification upon recapture. A biologist wants to use this method for a population census of desert mice. This will work if the _____.
A biologist waits a long time before resampling the population
B mice deliberately return because the traps contain food
C mice are territorial
D mice are recaptured in the same location using the same trapping methods

D mice are recaptured in the same location using the same trapping methods All of the other choices would result in the unequal probability of the capture of different individuals, so the mark-recapture method would not be valid.

When needed resources are unevenly distributed, organisms often show a(n) _____ dispersion pattern.
A clumped
B exponential
C density-dependent
D random

A clumped Individuals will be found in proximity to resources.

Herring gulls fiercely defend the areas around their nests in cliff-top breeding colonies. Within the colony, they would show a _____ dispersion pattern.
A clumped
B random
C dense
D uniform

D uniform

Pine trees in a forest tend to shade and kill pine seedlings that sprout nearby. This causes the pine trees to _____.
A grow in a random pattern
B increase exponentially
C grow in a clumped pattern
D grow in a uniform pattern

D grow in a uniform pattern The area shaded by each tree will determine pine tree distribution.

Chimpanzees have a relatively low birth rate. They take good care of their young, and most chimps live a long life. The chimp survivorship curve would look like a _____.
A line that slopes gradually upward
B line that slopes gradually downward
C line that drops steeply at first, then flattens out
D relatively flat line that drops steeply at the end

D relatively flat line that drops steeply at the end

A population will always grow exponentially _____.
A if it is a population with an equilibrial life history
B if there are no limiting factors
C if it is limited only by density-dependent factors
D until it reaches carrying capacity

B if there are no limiting factors Limiting factors determine the maximum number of individuals that can be supported by a given environment. In the absence of such factors, a population will reproduce at its maximum rate.

A population of mice has grown so rapidly that there are 2,400 individuals in an ecosystem that will support about 1,800 mice. The mouse population is most likely to _____.
A undergo niche separation to accommodate the extra mice
B undergo a dramatic decline in size, possibly to a stable level at or below 1,800 individuals
C continue to increase
D continue to have a birth rate that equals the death rate

B undergo a dramatic decline in size, possibly to a stable level at or below 1,800 individuals When N (population size) exceeds K (carrying capacity), not all members of the population will find sufficient resources to exist. The birth rate must decrease, the death rate must increase, or both.

The logistic growth model differs from the exponential growth model in that it _____.
A is J-shaped and the exponential growth model is S-shaped
B never shows the effects of population-limiting factors
C implies that population size stabilizes at K when the birth rate is zero
D expresses the effects of population-limiting factors on exponential growth

D expresses the effects of population-limiting factors on exponential growth In the logistic model, the term (K – N)/K represents the effects of population-limiting factors that depress the exponential growth tendency, rN, to a greater degree as population size approaches the carrying capacity.

No population can grow indefinitely. The ultimate size of any population is limited by _____.
A its birth rate
B the carrying capacity of its environment
C its r
D its death rate

B the carrying capacity of its environment Ecologists define carrying capacity as the maximum population size that a particular environment can support with no net increase or decrease over a relatively long period of time.

The cyclic growth exhibited by populations of snowshoe hares in the North American taiga most likely results from _____.
A fluctuations in the hare’s food resources
B hunting by humans
C predation by lynx and fluctuations in the hare’s food resources
D predation by lynx

C predation by lynx and fluctuations in the hare’s food resources Recent studies indicate that both factors are involved.

Which of these research topics would be considered an example of community ecology?

A Scientists studying the American bullfrog have reported that the longer a bullfrog remains in the tadpole stage, the greater the chance of its survival once it undergoes metamorphosis.
B A researcher found that the reproductive success of bumblebees decreased when the population density of honeybees increased. The decline in the number of bumblebees appeared to be a result of competition for nectar.
C An agricultural ecologist investigated the effect of fertilizers on corn crop yields.
D A graduate student collected information about the age structure of the black bear population in Wisconsin.

B A researcher found that the reproductive success of bumblebees decreased when the population density of honeybees increased. The decline in the number of bumblebees appeared to be a result of competition for nectar. This is an example of a study of interactions between populations, which is part of community ecology.

A community is composed of
A the factors that constitute an organism’s niche.
B living organisms and their nonliving environment.
C potentially interacting populations of different kinds of organisms.
D one species of organism living in a specific environment on Earth.

C potentially interacting populations of different kinds of organisms.

In tropical forests, there are plants known as ant-plants. These plants host ant colonies. When the ant colony is the species Petalomyrmex phylax, the presence of the ants protects the ant-plants from predation by herbivores. However, the ant species Cataulacus mckeyi takes advantage of the nesting place and nectar the plants provide without affording any protection to the plant. The interspecies interaction between the ant-plants and P. phylax is an example of _____ whereas the interaction between the ant-plants and C. mckeyi is an example of _____.

A competition … parasitism
B mutualism … competition
C herbivory … predation
D mutualism … parasitism

D mutualism … parasitism

An owl and a hawk both eat mice. Which of these describes the relationship between a hawk and an owl?
A mutualism
B competition
C predation
D parasitism

B competition

When two different populations in a community benefit from their relationship with each other, the result is called
A competition.
B parasitism.
C benefism.
D mutualism.

D mutualism.

If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap?

A Both species will coexist, provided the environment in the zone of overlap is different from that in either individual range.
B A new species will arise by hybridization.
C One species will take over most or all of the zone of overlap.
D Both species will coexist, provided the environment in the zone of overlap is similar to that of one of the individual ranges.

C One species will take over most or all of the zone of overlap.

Which of the following is an example of mutualism?

A On the bird feeders of many residents of southern Illinois, people can watch the fox squirrels and gray squirrels fight with each other for the bird seed, while the birds get scared away by the activity!
B Scratching with great vigor, the poor chipmunk tried to knock loose the tick stuck firmly to its ear.
C Twisting about like a high-flying acrobat, the gray flycatcher plucks moths from the air.
D Some biologists have observed Egyptian plover birds land on the open mouth of a Nile crocodile without being eaten and remove leeches stuck firmly to the crocodile’s gums.

D Some biologists have observed Egyptian plover birds land on the open mouth of a Nile crocodile without being eaten and remove leeches stuck firmly to the crocodile’s gums. In a mutualistic relationship, two species live closely together and benefit each other.

Which of the following is an example of predation?

A Losing weight quickly and without much energy, Hank went to see his doctor. After a series of tests, she diagnosed the problem. Hank had a tapeworm.
B During long migrations in the fall, huge flocks of geese seek out and settle in recently harvested cornfields, feeding on grain left scattered after the harvest.
C Feeding primarily on the same types of algae in small ponds, the tadpoles of wood frogs and leopard frogs compete with each other for meals.
D Sea anemones coating the shallow-water coral reefs in Australia feed on fish and shrimp that wander too close to their tentacles.

D Sea anemones coating the shallow-water coral reefs in Australia feed on fish and shrimp that wander too close to their tentacles.

Camouflage typically evolves as a result of

A interspecific competition.
B mutualism.
C herbivory.
D predation.

D predation.

Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. The process is called
A selection.
B coevolution.
C trophism.
D herbivory.

B coevolution.

Which of the following is an example of herbivory?

A Squirrels in the forests of Wisconsin hide away hickory nuts and acorns, which they will eat during the long, cold winter.
B In early spring, a rare warbler returns to southern Ontario to reproduce. However, this rare warbler struggles to find suitable nesting cavities in trees because these same locations are used by tree swallows and house wrens.
C The recent spread of West Nile virus has resulted from mosquitoes that feed on the blood of infected birds.
D Nitrogen-fixing bacteria help some legumes grow much faster than if the bacteria were absent.

A Squirrels in the forests of Wisconsin hide away hickory nuts and acorns, which they will eat during the long, cold winter.

Most plants have a variety of chemicals, spines, and thorns because the plants

A cannot run away from herbivores.
B feed on the organisms that try to eat them.
C are camouflaged into their surroundings.
D are relying upon Batesian mimicry.

A cannot run away from herbivores.

A hypothetical community on a barren mid-Atlantic island consists of two fish-eating seabirds (the booby and the noddy), the fungi and microorganisms that live on the birds’ dung, a tick that feeds on these two birds, a cactus, a moth that feeds on cast-off feathers, a beetle that lives on dung organisms, and spiders that eat the other arthropods. There are no other plants and no lichens. Which of the following choices incorrectly pairs a member of this assemblage with its position in the trophic structure?

A fungi, detritivores
B cactus, producer
C moth, detritivore
D booby, primary consumer

D booby, primary consumer

In a certain ecosystem, field mice are preyed on by snakes and hawks. The entry of wild dogs into the system adds another predator of the mice. Of the following, the most likely short-term result of this addition is
A migration of the hawks to another ecosystem.
B a tendency for hawks to prey on the dogs.
C an increase in snake population.
D a reduction in numbers of mice.

D a reduction in numbers of mice.

Examine Figure 37.9 in your textbook, which shows a food web. If the snake population were suddenly reduced because of a virus that kills only snakes, we would expect that the population of _____.
A cacti would suffer from increased herbivory
B owls would decrease
C mice would decrease
D hawks would increase dramatically

A cacti would suffer from increased herbivory Without the snakes to keep mice, squirrels, and other herbivores in check, there would be many more herbivores feeding on the area’s plant populations.

Which of the following represents a community with the greatest species richness?
A a plant community with four different species, each consisting of about 2,000 plants
B a plant community with four different species, each consisting of about 500 plants
C a plant community with seven different species – two species each consisting of about 10,000 plants and five other species consisting of about 200 plants each
D a plant community with 12 different species, in which each species consists of only about 100 plants

D a plant community with 12 different species, in which each species consists of only about 100 plants This community has the greatest number of species, the factor that determines species richness.

Without elephants, some of the grasslands in Africa would eventually become thickets or forests because elephants weed out trees and shrubs. Even though elephants make up a small percentage of the animals living on the grassland, the grassland would eventually cease to exist without them. In this community, elephants are _____.
A a keystone species
B a pioneer species
C an invasive species
D the dominant species

A a keystone species A keystone species is a species that has a greater impact on the community than would be expected based on its relative abundance or total biomass.

Which of the following processes does not occur in ecosystems?
A Energy flows through the system.
B Carbon is cycled between biotic and abiotic forms.
C The energy source that powers the system is used by consumers to make organic compounds.
D Producers convert light energy to chemical energy.

C The energy source that powers the system is used by consumers to make organic compounds.

A biology teacher takes fish, algae, pond weed, invertebrates, and bottom muck from a local pond and establishes them in an aquarium. When the system is stable, the teacher seals it into a large, airtight glass box and leaves the box in a sunny location. After three months, the organisms in the aquarium appear alive and healthy. Which of the following statements about the experiment is true?

A During the three months, the biomass of animal life was greater than the biomass of plant life.
B No energy has entered or left the glass box during the three months.
C Some of the energy in the system has moved from one organism to another during the three months.
D The air in the glass box contains no carbon dioxide.

C Some of the energy in the system has moved from one organism to another during the three months.

Which of the following ecosystems would probably have the highest primary productivity? Assume that we are comparing similar sizes of each ecosystem.
A a tropical coral reef
B an ecosystem with only primary consumers
C the open ocean
D a desert environment

A a tropical coral reef A tropical coral reef system exposes many primary producers to high levels of sunlight throughout the year. This opportunity for extended photosynthesis generates tremendous biomass.

For a given area and time period, the amount of solar energy converted to chemical energy in organic compounds is called
A secondary production.
B secondary succession.
C primary production.
D primary succession.

C primary production.

In an ecosystem where 500,000 kcal of sunlight is available for producers, approximately how much chemical energy will be contained in secondary consumers?
A 5,000 kcal
B 5 kcal
C 50 kcal
D 500 kcal

C 50 kcal This is how much energy is contained in secondary consumers. About 10% of available biomass in primary consumers is converted to biomass in secondary consumers.

In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level?
A a tenth as much
B ten times as much
C half as much
D twice as much

B ten times as much

Our current ability to feed the people of the world would improve if people ate a diet that only consisted of _____.
A secondary consumers
B tertiary consumers
C producers
D primary consumers

C producers Eating producers requires less land and energy than eating equal volumes of meat.

Which of the following is an abiotic reservoir?
A the fish in the sea
B birds
C soil
D an algal bloom

C soil This is an abiotic reservoir that is a storage point for many chemicals in between their use in living organisms.

The main cause of the recent increase in the amount of carbon dioxide in Earth’s atmosphere is _____.
A an increase in the amount of radiation absorbed by the atmosphere
B additional respiration by the rapidly growing human population
C the burning of larger amounts of wood and fossil fuels
D increased worldwide standing crop biomass

C the burning of larger amounts of wood and fossil fuels There are not enough primary producers to keep up with the loading of carbon in the atmosphere from the burning of wood and fossil fuels.

What type of population interaction benefits neither population?
A competition
B predation
C mutualism
D parasitism

A competition In all but competition, at least one species benefits. In competition, both species are trying to utilize the same limiting resource.

If the niches of two species are very similar, which of the following is true?
A A mutualistic relationship will exist.
B Interspecific competition will be mild.
C Competition between the two species will be severe.
D The two species are mutually interdependent.

C Competition between the two species will be severe. Two species with similar needs for the same limited resources cannot coexist in the same place.

Herbivores are _____.
A detritivores
B primary consumers
C producers
D secondary consumers

B primary consumers

Photosynthetic organisms are called _____.
A heterotrophs
B autotrophs
C consumers
D herbivores

B autotrophs Autotrophs are generally photosynthetic organisms that use light energy to synthesize sugars and other organic compounds.

When you eat an apple, you are serving as a _____.
A primary consumer
B producer
C secondary consumer
D tertiary consumer

A primary consumer

The main detritivores in an ecosystem are _____.
A plants and fungi
B plants and animals
C fungi and prokaryotes
D prokaryotes and animals

C fungi and prokaryotes Fungi and prokaryotes are the groups most involved in the conversion of organic compounds to inorganic nutrients.

Species richness and relative abundance define the _____ of a community.
A food web
B ecological niche
C species diversity
D food chain

C species diversity

In ecosystems, organisms at the highest trophic levels usually contain less collective biomass than the organisms at lower trophic levels because _____.
A organisms are inefficient at converting the energy they consume to biomass
B top-level predators use so much energy to catch their food
C biomass shrinks as it rises
D producers (for example, plants) tend to be heavier than consumers (for example, birds)

A organisms are inefficient at converting the energy they consume to biomass Ecological efficiencies vary greatly among organisms, but an estimate is that 80-95% of the energy in one level is not available to the next.

A study of metabolic rates in a terrestrial community showed that the energy released by respiration exceeded the energy captured in photosynthesis. Which of the following situations is most likely?
A A climax community has been reached.
B The second law of thermodynamics (in a closed system, there is a general tendency toward disorder) is not in effect.
C Community biomass is increasing.
D Community biomass is decreasing.

D Community biomass is decreasing. Net primary productivity is the difference between the yield of photosynthesis and the consumption of organic fuel in respiration. Primary productivity can be expressed as the biomass of vegetation added to an area of the ecosystem per unit of time. If the energy released by respiration exceeds the energy captured in photosynthesis, biomass decreases.

In general, the biomass in an ecosystem will be greatest at the trophic level comprising _____.
A producers
B herbivores
C tertiary consumers
D primary consumers

A producers

The relationship between biomass and primary productivity is that _____.
A biomass is the rate of primary productivity
B biomass is the natural log of primary productivity
C primary productivity is the rate at which biomass is produced
D biomass is the inverse of primary productivity

C primary productivity is the rate at which biomass is produced Primary productivity is the amount of chemical energy that autotrophs produce from light energy during a given period of time. Biomass is the dry weight of organic matter produced by primary productivity.

In any food chain, the top level of consumers is quaternary (fourth). Why are there almost never any fifth-level consumers?
A Quaternary consumers are too large and fierce to be prey for other animals.
B There is not enough available energy to sustain a fifth level.
C The fourth-level consumers are already occupying the best territories.
D Consumers tend to eat a broad variety of prey, and so we have food webs rather than food chains.

B There is not enough available energy to sustain a fifth level.

Which of the following best describes the base of a pyramid of production?
A It represents the energy available to secondary consumers.
B It contains the energy captured by photosynthesis.
C It contains the energy left after the producers have died.
D Its size depends on the energy available from detritivores

B It contains the energy captured by photosynthesis.

The biggest difference between the flow of energy and the flow of chemical nutrients in an ecosystem is that _____.
A the amount of energy is much greater than the amount of nutrients
B energy is recycled, but nutrients are not
C organisms always need nutrients, but they do not always need energy
D nutrients are recycled, but energy is not

D nutrients are recycled, but energy is not Chemical nutrients can be recycled through an ecosystem via biogeochemical cycles. Energy is lost from an ecosystem as a result of respiration.

Bacteria are especially important in making _____ available to plants.
A nitrogen
B phosphorus
C water
D carbon

A nitrogen Nitrogen fixation by prokaryotes makes nitrogen available to plants.

_____ is the goal of developing, managing, and conserving Earth’s resources in ways that meet the needs of people today without compromising the ability of future generations to meet theirs.
A Community ecology
B MSY (maximum sustainable yield)
C Organic farming
D Sustainability

D Sustainability