Ch.25 Ecology Verified Test Bank

Stern's Introductory Plant Biology, 14e (Bidlack)

Chapter 25 Ecology

1) All the living organisms plus the environmental factors present in a given area constitute

A) a plant community.

B) a biotic community.

C) an ecosystem.

D) a food chain.

E) a food web.

2) Which of the following estimates or calculations are made with respect to populations?

A) numbers of individuals

B) density

C) biomass

D) geographical range

E) All of these answers are correct.

3) In an energy pyramid of an ecosystem ________.

A) there is much more energy at the top than at the bottom.

B) there is little reduction in energy retained from one level to the next.

C) secondary consumers are sustained with less energy than primary consumers.

D) there is much more energy at the bottom than at the top.

E) the individual components do not function in a regulatory fashion.

4) Chemicals produced by higher plants that kill or inhibit disease fungi or bacteria are known as ________.

A) allelopathic compounds

B) herbicides

C) immunotoxins

D) antibiotics

E) phytoalexins

5) The factors that allow organisms to grow, compete, reproduce, and perpetuate the species in a particular area are part of a field of inquiry called

A) physiology.

B) ecology.

C) taxonomy.

D) biochemistry.

E) morphology.

6) When a grass plant is eaten by an herbivore, which in turn is eaten by a carnivore, this is an example of a

A) symbiosis.

B) autotrophic web.

C) food chain.

D) trophic level.

E) ecotype.

7) The ________ or living component of any environment includes all individuals of each species that interact in that habitat.

A) biotic

B) abiotic

C) population

D) ecosystem

E) ecotype

8) Components of the abiotic environment include ________.

A) predators

B) pollinating species

C) all living species

D) seasonal temperatures

E) All of these answer choices are correct.

9) A ________ is a group of individuals of the same species, occupying the same region and potentially interacting with each other.

A) community

B) ecosystem

C) population

D) food chain

E) family group

10) Features of plants and animals that allow them to survive and reproduce in their environment are considered ________. One example of this is CAM photosynthesis in desert plants.

A) advantages

B) allocations

C) modifications

D) mutations

E) adaptations

11) The foremost ecosystem decomposers are

A) scavengers.

B) primary consumers.

C) bacteria and fungi.

D) producers.

E) insects.

12) More than 100 years ago Thomas Belt called attention to the symbiotic association between Acacia shrubs and ants. Acacia encouraged the association by providing food for the ants and a home in ________.

A) long tendrils

B) rhizomes

C) small tubers

D) large hollow thorns

E) None of these answers are correct.

13) Trophic efficiency

A) is the percentage of available energy actually transferred from one trophic level to the next.

B) is relatively high in aquatic ecosystems averaging about 10% from one tropic level to the next.

C) is lower in terrestrial ecosystems when compared with aquatic ecosystems.

D) tells us that secondary consumers get far less energy than if they were a primary consumer.

E) All of these are correct statements about trophic efficiency.

14) In exchange for food and housing, the ants in the ant–Acacia symbiotic association

A) act as herbivores on the Acacia.

B) neither benefit nor harm the Acacia.

C) attack herbivores that attempt to eat Acacia leaves.

D) kill plants that attempt to compete with the Acacia for water and nutrients.

E) both attack herbivores and kill competing plants.

15) Which series illustrates the correct hierarchy in relationship to each other in the series?

A) biosphere, ecosystem, population, community

B) biosphere, ecosystem, community, population

C) biosphere, community, population, ecosystem

D) biosphere, population, community, ecosystem

E) None of these answers are correct.

16) On average, plants capture and convert approximately ________ of the energy in sunlight reaching the earth's surface.

A) 1%

B) 10%

C) 20%

D) 50%

E) 100%

17) Movement of materials through any community can be tracked by developing a/an ________ for that community.

A) energy pyramid

B) photosynthetic pathway

C) food web

D) food chain

E) soil profile

18) The reproductive strategy of any plant species is regarded as ________.

A) maintaining the pollinator supply

B) the seed bank

C) the length of its lifespan

D) its life history strategy

E) the ratio of photosynthesis to cellular respiration

19) Weedy plant species are ________.

A) usually large, long-lived plants that occur in stable habitats

B) usually fast growing, small annuals that reproduce quickly

C) usually woody

D) usually herbaceous perennials

E) plants that usually require two growing seasons to complete their life cycle

20) Nitrogen fixation refers to ________.

A) the conversion of organic proteins to nitrogen gas by bacteria

B) chemical conversion of nitrogen gas to ammonia in chemical fertilizer production

C) conversion of atmospheric nitrogen gas to ammonia or nitrates by bacteria

D) use of atmospheric nitrogen by plants

E) the presence of nitrogen in proteins of living organisms

21) When nitrogen from the air is converted to ammonia or other nitrogenous compounds by microorganisms, it is said to be

A) nitrosofied.

B) nitrified.

C) oxidized.

D) ammonified.

E) fixed.

22) Microorganisms that gain access to various plants, particularly legumes, usually do so through or as a result of which of the following?

A) root hair

B) osmosis

C) active transport

D) imbibition

E) None of these answers are correct.

23) Loss of nitrogen from the soil occurs as a result of which of the following?

A) erosion

B) leaching by water

C) harvesting

D) fire

E) All of these answers are correct.

24) Which of the following is the term used for bacteria that use nitrates instead of oxygen in their respiration?

A) nitrifying

B) denitrifying

C) nitrogen-fixing

D) hardpan bacteria

E) None of these answers are correct.

25) As much as 90% or more of the carbon dioxide needed throughout the earth for photosynthesis is produced by

A) animals.

B) broad-leaved vegetation.

C) aquatic algae.

D) decay bacteria and fungi.

E) coniferous forests.

26) Loss of nitrogen from the soil due to a fire may be offset by which of the following?

A) nitrogen-fixing soil bacteria

B) a decrease in fungi that cause plant diseases

C) mineral-rich ash produced by the fire

D) nitrogen fixed by lightning

E) All of these answers are correct.

27) Carbon dioxide comprises approximately what percentage of the atmosphere?

A) 13.38%

B) 3.8%

C) 0.38%

D) 0.038%

E) 0.138%

28) Carbon dioxide is important to plants because it acts as the carbon source in which process?

A) respiration

B) fermentation

C) glycolysis

D) photosynthesis

E) active transport

29) Plants obtain their nitrogen supply directly from

A) atmospheric nitrogen.

B) nitrates or ammonia.

C) proteins in the soil.

D) fertilizers.

E) soil bacteria.

30) The structure produced when nitrogen-fixing bacteria infect legume plants and forms a symbiotic relationship is called a(an) ________.

A) adventitious root

B) crown gall

C) root nodule

D) secondary root

E) legume node

31) Which of the following is an example of secondary succession?

A) reforestation after a fire

B) successive development of vegetation on a lava flow after it has cooled

C) successive development of vegetation in a pond created by a beaver dam

D) successive development of vegetation on a rock pile after an avalanche

E) None of these answers are correct.

32) ________ and ________ are the two common gases that lessen re-radiation of heat back into the space and, hence, contribute to increasing temperatures on Earth.

A) CFCs (chlorofluorocarbons); halons

B) Carbon dioxide; methane

C) Sulfur dioxide; nitric acid

D) Nitrogen gas (N2); ammonia

E) Water vapor; nitrogen gas (N2)

33) Events predicted to occur with increasing global temperatures include ________.

A) sea level rising, resulting in flooding low-lying coastal areas

B) limited impact on human populations

C) no disruption of food producing acreage

D) decrease in global desert acreage

E) All of these answer choices are correct.

34) A producer is an organism that carries on photosynthesis.

35) The foremost decomposers in ecosystems are the roots of plants.

36) Energy is normally completely recycled in an ecosystem.

37) The total mass of consumers is largely determined by the total mass of food made available by the producers.

38) Phenology refers to the timing of developmental events, such as germination, flowering and seed production, in the life cycle of a plant

39) Climax vegetation always consists of some type of trees.

40) Fires benefit both grassland and forest vegetation by converting dead organic materials to nutrient-rich ash.

41) Hydrophyte plants require running water for pollination.

42) Kudzu, tamarisk, and the agents that cause Dutch Elm disease and American Chestnut blight are examples of how introduction of foreign species can disrupt natural ecosystems.

43) Primary succession usually takes place in areas previously covered with vegetation.

44) Eutrophication refers to the process of decay.

45) The majority of chaparral species, both woody and herbaceous, are so adapted to fire that their seeds will not germinate, as a rule, until fires remove accumulated litter.

46) Carbon dioxide is taken up during respiration and the decay process.

47) Acid deposition lands on plants and lowers the pH of lakes, ponds, and soil. Plants are harmed when acid falls on them but are not affected by changes in pH of the soil or water in which they grow.

48) Succession after a disturbance produces exactly the same plant communities as had existed before the disturbance.

49) Humans have little impact on water, carbon, and nitrogen cycles in the biosphere.