Download Ecology Test

Ecology Test
Study Guide
I.
What is ecology?
a. Define ecology
Scientific study of the interactions of organisms with each other and their environment.
b. List the different levels of organization in ecology.
i. Individual
ii. Population
iii. Community
iv. Ecosystem
v. Biome
vi. Biosphere
c. Describe the difference between biotic and abiotic factors.
Biotic – factors of an ecosystem that are living or once living
Abiotic – factors of an ecosystem that are non-living such as temperature, precipitation, humidity and
amount of sunlight.
II.
Energy, Producers, and Consumers
a. Distinguish the difference between autotrophs and heterotrophs.
Autotrophs make their own food (food = sugar = glucose).
Heterotrophs cannot make their own food and must take in food from their environment.
b. Define primary producers.
Primary producers make food using sunlight through photosynthesis.
c. List the 6 different types of consumers.
i. Carnivores
ii. Herbivores
iii. Omnivores
III.
iv. Scavengers
v. Detritivores
vi. Decomposers
Energy Flow in an Ecosystem
a. Distinguish the difference between food chains and food webs.
Food chains show the flow of energy through an ecosystem by one feeding relationship.
Food webs show the flow of energy through an ecosystem by ALL feeding relationships.
b. Explain the role/importance of decomposers.
Decomposers break down dead materials and return nutrients back to the environment.
c. Define trophic level.
Trophic levels are the level at which an organism feeds (obtains energy).
d. Identify the 3 types of ecological pyramids.
Energy pyramid
Biomass pyramid
Numbers pyramid
e. Define the “Rule of Ten”
Only ten percent moves up a trophic level because 90% gets used up.
f. Define biomass.
Biomass is the amount of living tissue.
IV.
Cycles of Matter
a. What are biogeochemical cycles?
The cycles of nutrients through the environment are water, carbon, nitrogen, and phosphorus cycle.
b. Describe the water cycle.
Water precipitates, evaporate, and condenses to form clouds. Some water will be drawn up by plants and
re-enter the atmosphere through transpiration. Water can also enter rivers and streams as run-off. Water
can also be absorbed by the ground (infiltration/percolation) to become groundwater.
c. Describe the carbon cycle.
Carbon in carbon dioxide is absorbed by plants for photosynthesis and put into glucose. Glucose is broken
down through cellular respiration and CO2 is released back into the atmosphere.
d. Describe the nitrogen cycle.
Nitrogen in nitrogen gas is “fixed” by nitrogen fixing bacteria into the soil as ammonium. Nitrifying bacteria
convert it to nitrates which are then absorbed by plants. Denitrifying bacteria can release nitrates back into
the atmosphere as nitrogen gas.
e. Describe the phosphorus cycle.
Phosphates are released from rocks from weathering and erosion. Phosphates are then absorbed by plants
and transferred to other organisms through feeding relationships. When organisms die, their bodies are
fossilized over a long period of time back into rocks.
V.
Climate
a. Define climate.
Climate is the long-term predictable pattern of temperature and precipitation of an ecosystem.
b. Describe the greenhouse effect.
Greenhouse gases trap heat after allowing visible light to enter the atmosphere. This trapped heat increases
the temperature of the Earth’s surface.
VI.
Niches and Community Interactions
a. Explain the competitive exclusion principle.
Two species cannot occupy the same niche in the same habitat at the same time. Because of competition,
the less competitive species does not survive.
b. Describe the impact of a keystone species.
The keystone species is the species that can cause a dramatic change in the structure of a community if it is
disturbed.
c. Define symbiosis.
Symbiosis is a relationship between organisms of different species where at least one benefits.
d. Provide examples and explanations for the three symbiotic relationships.
Mutualism – both benefit.
Commensalism – one benefits, the other is not affected.
Parasitism – one benefits, the other is harmed.
VII.
Succession
a. Define succession.
Ecological succession is the predictable sequence of events in an ecosystem after a major disturbance
b. Describe the difference between primary and secondary succession.
Primary Succession – succession that begins with bare rock (no soil) (volcano, landslide)
Secondary Succession – succession that begins with soil (forest fire, clear cutting
c. Describe the role of a pioneer species.
Pioneer species are organisms that start or initiate a community in an ecosystem such as moss and lichen.
VIII. Biomes
a. Identify the biome with…
i. Most biodiversity – tropical rainforest
ii. Canopy and understory – tropical rainforest
iii. Least amount of rainfall – desert
iv. Coniferous trees – coniferous forest
v. Deciduous trees – temperate forest (dry/rain)
vi. Permafrost - tundra
IX.
Aquatic Ecosystems
a. Identify the three types of aquatic ecosystems.
Freshwater, estuary and marine
b. Identify three types of freshwater ecosystems.
Rivers and streams; lakes and ponds; wetlands
c. Describe the importance of estuaries.
Breeding ground and nurseries of many animals
X.
Changing Landscape
a. Define sustainable use.
The responsible use of resources to maintain
b. Distinguish renewable and nonrenewable resource.
renewable resources can be replaced in a relatively short period of time.
non renewable resources cannot be replenished or replaced once they are used.
XI.
Using Resources Wisely
a. Describe biomagnification.
Biomagnification is also known as biological magnification. Chemicals such as DDT can accumulate in the
tissues of organisms as it moves up the trophic levels. The harmless low levels of chemicals at the bottom of
an energy pyramid will actually accumulate to harmful levels at the higher trophic levels.
b. Identify the major forms of air pollution.
The major forms of air pollution are acid rain, smog, greenhouse gases, and particulates.
XII.
Biodiversity
a. Describe the importance of biodiversity.
Biodiversity is tantamount to genetic diversity. With genetic diversity, there is more stability in a population
protecting it from possible extinction from disease.
b. Identify an invasive species in PA.
i. Plant – bamboo, purple loosestrife, tree of heaven, marijuana, common reed (phragmites)
ii. Animal – hogs, zebra mussels, emerald ash borer, asian longhorned beetle, red-eared slider
XIII. Meeting Ecological Challenges
a. Define ecological footprint.
The ecological footprint is also known as the carbon footprint. This is the impact individuals and populations
have on the use of resources as well as the production of waste.