Ecosystem Balance

Test Review

Question 1 (6 Points)• List, in order, the 6 communities in primary

succession from the pioneer community to the climax community

• a. Pioneer Community: ______________• b. _______________________________• c. _______________________________• d. _______________________________• e. _______________________________• f. Climax Community: _______________

Lichen

Grasses

Shrubs

Heath MatPine Trees

Hardwood Trees

Question 2 (4 Points)• Besides humans, what are 4 factors that can

influence the stability of an ecosystem?

• Answer:• Biotic, abiotic, patterns of energy, nutrient

cycling, communities, and food webs

Question 3 (3 Points)• How does primary succession differ from

secondary succession?

• Answer:• Primary – organisms and soil is gone• Secondary – only organisms gone

Question 4 (2 Points)• In what biome do we live?

• Answer: Deciduous Forest

Question 5 (2 Points)• Which biomes have the most biomass?

• Answer: Forest

Question 6 (2 Points)• Which biome covers the largest land area?

• Answer: Desert

Question 7 (2 Points)• What is a biome?

• Answer: Largest category scientists use to classify ecosystems

Question 8 (2 Points)• Why are herbivores not considered to be

parasites?

• Answer: They don't live on or in the bodies of plants

Question 9 (2 Points)• Which symbiotic relationship helps one

species and does not harm or help the other?

• Answer: Commensalism

Question 10 (1 Points)• A relationship between species in which

one species benefits and the other is harmed is called?

A. Parasitism

B. Commensalism

C. Mutualism

D. Symbiosis

Question 11 (1 Points)• Elephants and rhinos tolerate the small

birds that ride their backs and eat insects o their skin. The relationship between the elephants and the birds is an example of?

A. Parasitism

B. Commensalism

C. Mutualism

D. Symbiosis

Question 12 (1 Points)• An increase in a predator population will

directly result in

A. Decline in prey population

B. Decreased predation

C. Starvation

D. Ecosystem balance

Question 13 (1 Points)• The size of the host population controls

A. the geographic range of parasites

B. important bodily functions

C. the size of the parasite population

D. the size of the prey population

Question 14 (1 Points)• You would be most likely to find populations

of host organisms parasitized when

A. they have little to eat

B. they cannot escape

C. they are diseased

D. they are overcrowded

Question 15 (1 Points)• Mutualism is often the result of

A. coevolution

B. symbiosis

C. fierce competition

D. cooperation

Question 16 (1 Points)• Parasitism is an example of

A. coevolution

B. symbiosis

C. ecosystem balance

D. predation

Question 17 (1 Points)• A defining characteristic of a climax

community is that it is essentially

A. sedimented

B. stable

C. forested

D. grassy

Question 18 (1 Points)• The first organisms to colonize a newly

formed lifeless habitat are part of

A. a shoreline ecosystem

B. secondary succession

C. primary succession

D. mature communities

Question 19 (1 Points)

• Aquatic succession typically begins

A. on the surface of a lake

B. at the shoreline of a lake

C. at the bottom of a lake

D. in the middle of a lake

Question 20 (1 Points)

• Which type of disturbance would most likely result in secondary succession

A. rainfall creates a new lake at the top of a

mountain

B. glacier retreats leaving barren rock

C. a volcanic eruption

D. an earthquake

Question 21 (1 Points)

• Why do new species often form on new islands?

A. New islands have a lot of vegetation

B. There is increased competition

C. Their populations explode

D. They evolve to fill new niches

Question 22 (1 Points)• When applied to ecology, what does the

new field of mathematics called chaos theory imply?

A. Ecosystems are really not balanced

B. Organisms are constantly changing to meet new conditions

C. One small change in an ecosystem can lead to drastic results

D. Ecosystems are really not balanced

Question 23 (1 Points)

• The kind of biome that will develop in an area is determined mainly by temperature and

A. pressure habitats

B. precipitation

C. average wind speed

D. organisms present

Question 24 (1 Points)

• The biome with the greatest species diversity is the

A. rain forest

B. deciduous forest

C. wetlands

D. tundra

Question 25 (1 Points)

• Which of the following biomes receives the least amount of rainfall?

A. tropical dry forest

B. tundra

C. chaparral

D. shrubland

Question 26 (1 Points)

• In which biome does fire play an important part in maintaining ecosystems?

A. tropical dry forest

B. tundra

C. chaparral

D. shrubland

Good Luck!

• And STUDY!!!