A) a population B) a communityC) an ecosystem D) the biosphere

1. The diagram below represents many species of plantsand animals and their surroundings.

What does the diagram best represent?

A) the climax stage B) the biosphereC) a population D) a biotic community

2. The portion of Earth in which all life exists is known as

A) community B) ecosystemC) population D) biosphere

3. Which level of biological organization includes thegreatest total number of species?

A) The water temperature would rapidly decrease.B) The process of respiration in the snail would

decrease.C) The rate of reproduction of the fish would be

affected.D) The organisms would probably survive because

materials would cycle.

4. Which statement most accurately predicts what wouldhappen in the aquarium shown below if it were tightlycovered and maintained in natural light for one month?

5. Base your answer to the following question on A pondecosystem is represented in the diagram below.

A) water B) consumersC) sunlight D) plants

Energy for this ecosystem originally comes from

A) hurricanes, packs of wolves, and temperatureB) blizzards, heat waves, and swarms of grasshoppersC) droughts, floods, and heat wavesD) species of fish, number of decomposers, and supply

of algae

6. Abiotic factors that could affect the stability of anecosystem could include

A) an ecosystem B) a communityC) a food web D) a population

7. A group of organisms within a given area capable ofinterbreeding and producing fertile offspring undernatural conditions is called

8. Base your answer to the following question on The diagram below shows organisms in and around a pond.

A) heterotroph B) community C) population D) producer

Which ecological term refers to all the organisms shown in the diagram?

A) reproduce at different times of the yearB) are the same sizeC) occupy different ecological nichesD) are active at night

9. Two species of animals with a similar appearance live inthe same habitat but do not compete for food. This isbecause they most likely

A) mold grows on a tree that has fallen in the forestB) chipmunks and squirrels eat sunflower seeds in a

gardenC) a crow feeds on the remains of a rabbit killed on

the roadD) a lion stalks, kills, and eats an antelope

10. Competition between two species occurs when

11. The feeding niches of three bird species are shown inthe diagram below.

A) less competition for foodB) fewer abiotic resources for each bird speciesC) fewer biotic resources for each bird speciesD) less energy available as the birds feed higher in the

tree

What is the advantage of these different feeding nichesfor the birds?

A) a loss of biodiversityB) an increase in ecological successionC) a lack of differentiationD) an increased carrying capacity

12. Researchers have reported that the number of differentspecies of fish found in certain areas of the ocean hasbeen greatly reduced over the past 50 years. Thissituation is an example of

A) 1 B) 2 C) 3 D) 4

13. The diagram below represents a cycling of materials.

Which row in the chart below shows the substancesrepresented by X and Y?

A) water B) energyC) oxygen D) carbon

14. In an ecosystem, which component is not recycled?

15. An ecosystem is represented below.

A) the organisms labeled A outnumber the organisms labeled BB) the organisms labeled A are equal in number to the organisms labeled BC) the type of organisms represented by B are eliminatedD) materials cycle between the organisms labeled A and the organisms labeled B

What would make this ecosystem self-sustaining?

A) maintenance of soil fertility in an ecosystemB) transfer of materials in the

carbon-hydrogen-oxygen cycleC) transfer of nitrogen through a food chainD) distribution of minerals in an ecosystem

16. The exchange of respiratory gases and the synthesis oforganic compounds by autotrophs are processes that aredirectly involved in the

A) respiration and photosynthesis, onlyB) transpiration and excretion, onlyC) respiration, photosynthesis, evaporation, and

condensation, onlyD) respiration, photosynthesis, transpiration,

excretion, evaporation, and condensation

17. Which processes are involved in the water cycle?

A) reproductive cycles of animalsB) recycling of inorganic compoundsC) flow of energyD) transport of groundwater

18. The soil on a farm can very quickly become depleted ofthe minerals essential to plants because harvesting ofcrops can interfere with the

A) decomposer B) producerC) herbivore D) carnivore

19. The process illustrated in the sequence below occursconstantly in the biosphere.

Which type of organism is most likely represented by X?

20. Organisms from a particular ecosystem are shownbelow.

A) Organism 2 is heterotrophic.B) Organism 3 helps recycle materials.C) Organism 4 obtains all of its nutrients from an

abiotic source.D) Organism 5 must obtain its energy from organism

1.

Which statement concerning an organism in thisecosystem is correct?

A) predator-preyB) consumer-producerC) parasite-hostD) autotroph-heterotroph

21. Puppies are often given medicine to eliminateroundworms from their intestines. These wormsconsume some of the food the puppies have digested.The worms and the puppies represent a relationshipknown as

A) commensalism B) mutualismC) parasitism D) saprophytism

22. A symbiotic relationship exists between two organismsof different species. If only one organism benefits fromthe relationship and the other is not harmed, therelationship is known as

23. Base your answer to the following question on the diagram below and on your knowledge of biology.

A) mutualism B) prey C) saprophytism D) host

Which term belongs in area A?

A) snake eating a birdB) tree absorbing mineralsC) fungus breaking down wastesD) deer eating grass

24. A relationship between a consumer and producer is bestillustrated by a

A) an increase in the number of carnivore speciesB) a decrease in new predators migrating into the

ecosystemC) a decrease in the size of decomposersD) an increase in the number of herbivores

25. The removal of nearly all the predators from anecosystem would most likely result in?

A) an increase in the number of clams B) a decrease in the number of water plantsC) an increase in the number of crabs D) a decrease in the number of crayfish

26. A food web is represented below.

When water used to cool machinery is returned to a river, it raises the river water temperature.

This causes a sharp decline in small invertebrate populations. Based on the food web, a likely consequenceof this change would be

A) A B) B C) C D) D

27. The diagram below represents a food web.

Which species would most likely be a decomposer?

Base your answers to questions 28 and 29 on the food web below and on your knowledge of biology.

A) mouse B) hawkC) snake D) frog

28. A decrease in the grass population will mostimmediately decrease the available energy for the

A) grass and trees B) mouse, rabbit, and cricketC) deer and mountain lion D) frog, snake, and hawk

29. Which organisms are carnivores?