Ecology Review
1. Review the following terms. Write out definitions for the terms that you would be UNSURE of defining on
a test.
Abiotic – the non-living physical and chemical components of an ecosystem
Atmosphere – the layer of gases surrounding Earth
Biotic – living things, their remains, and features etc
Biosphere – the zone around the earth in which life can exist
Bioaccumulation – the concentration of a substance in the body of an organism
Biodiversity – the variety of species in an ecosystem
Biogeochemical – series of cycles that involve both living organisms and earth processes
Biome – geographical region defined by climate and share biotic and abiotic factors
Biotic potential – maximum # of offspring a species can could produce with unlimited resources
Broad-spectrum pesticide – a pesticide effective against many types of pests
Carbon cycle – process of cycling carbon through our environment (combustion, photosynthesis)
Carnivore – species that only eats meat
Carrying capacity – maximum # of species that can be supported in an ecosystem
Cellular respiration – process by which sugar and oxygen are used to produce carbon dioxide and water
Community – a group of populations in an ecosystem
Consumer – feeds on producers or other consumers for survival
Corel reef – an ecosystem found in warm shallow oceans and support a large variety of oceans
Decomposer – breaks down detritus to release nutrients back into soil
Denitrification – bacteria converts nitrates into nitrites
Ecology – the study of living things and their interaction with non-living things
Estuary – partially enclosed body of water where fresh and salt water mix
Eutrophic – shallow bodies of water containing high levels of nutrients
Food web – a representation of the feeding relationships within an ecosystem
Fertilizer – a variety of nutrients used to enhance the production and maintenance of different species
Food chain – a sequence of organisms and who they are feeding on
Greenhouse gases – gases in the atmosphere that trap in heat and radiation
Habitat – a place in an ecosystem in which a species lives
Herbivore – a species that only eats plants
Hydrosphere – all of the earth’s water in solid, liquid and gas form
Inorganic – does not contain the combination of carbon and hydrogen atoms
Intertidal zone – a zone that is part time terrestrial and part time aquatic
Limiting factor – any factor that places an upper limit on the size of population
Lithosphere – all the Earth’s solid outer layer
Mangrove – communities that have adapted to live at and beyond the water’s edge
Narrow-spectrum pesticide – a pesticide effective against only a few types of pests
Niche – a species role in their ecosystem
Nitrate – usable form of nitrogen
Nitrogen cycle – a cycle in which nitrogen moves from an unusable form to a usable form and then back to an
unusable form
Nitrogen fixation – process of changing nitrites into nitrates
Nutrient – a chemical essential to living things
Oligotrophic – deep bodies of water containing very little nutrient content
Organic – contains the combination of carbon and hydrogen atoms
Population – the total number of one species in an ecosystem
Photosynthesis – the process in which sunlight is converted into chemical energy
Pesticide – chemicals used to control pests and increase yields
Pest – a species that is considered to be an annoyance to another species
Permafrost – a permanent layer of frozen soil
Primary consumer – feeds and gains energy from producers
Producer – creates its own food using energy from the Sun
Secondary consumer – feeds an gains energy from primary consumers and other secondary consumers
Tolerance range – a range in which species are able to adapt and survive
Trophic level – categorizing things and how they gain their energy
2. Draw an ecosystem that contains a lithosphere, atmosphere, hydrosphere and biosphere.
3. List and describe the five classifications for species at risk. Provide an example for each.
Extinct - A species that is not found anywhere.
Endangered - A species that is close to extinction in Canada or in a significantly large location
Extirpated - Any species that no longer exists in one part of Canada, but can be found in others
Threatened - Any species that is likely to become endangered if certain factors are not reversed
Special Concern - Any species that is at risk because of low or declining numbers at the fringe of
its range or in some restricted area
4. Identify each of the following as a population or a community? Explain your reasoning.
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deer (population; one species)
Niagara Falls (community; contains several species)
mice (population; one species)
cedar tree (population; one species)
rotting wooden log (community; contains several species)
Toronto (community; contains several species)
zoo (community; contains several species)
farm (community; contains several species)
5. List 4 abiotic factors and 4 biotic factors.
Abiotic – light, temperature, wind, water
Biotic – food, # of predators, diseases, ability to compete for resources
6. How many trophic levels can be found in an ecosystem? Provide a species from each.
Trophic level 1 (autotrophs; plants)
Trophic level 2 (primary consumers; rabbit)
Trophic level 3 (secondary consumers; blue jay)
Trophic level 4 (tertiary consumers; hawk)
7. Draw a food chain and a food web.
Food chain
Food web
8. In your Gizmo on the “food chain” you had an ecosystem that contained hawks, snakes,
rabbits, and grass.
a) Which of these species are producers and which are consumers?
- producer; grass consumer; rabbits, snakes, grass
b) What happened when you wiped out the hawk population?
- snakes increase; decline in rabbits; increase in grass; hawk population recovers; equilibrium
c) What happened when you wiped out the snake population?
- hawk population decreased; increase in rabbits; decrease in grass; snake recovers; equilibrium
9. Describe the ecological niche of a grasshopper.
- plant eating insects; serve as food for birds, lizards, spiders and rodents, found in grassy areas.
10. List and provide an example of the THREE different ecological pyramids
Pyramid of Energy
Pyramid of Numbers
Pyramid of Biomass
11. What is the difference between organic and inorganic matter?
See definitions
12. Explain the role of carbon in photosynthesis and cellular respiration.
Photosynthesis
Reactants
Products
6CO2
+ 6H2O +
light
→
C6H12O6
+ 6O2
Carbon dioxide + water + light energy → sugar (glucose) + oxygen
Cellular respiration
Reactants
Products
C6H12O6
glucose
+
+
oxygen
6O2
→
→
water
6H2O +
6CO2
+ carbon dioxide
13. Describe five different ways in which carbon can be cycled through our environment.
- combustion, burning fossil fuels, volcanoes, photosynthesis, respiration, mining etc.
14. Explain how nitrogen gets from an unusable form in our atmosphere into the human
body.
- nitrogen from our atmosphere undergoes a change when lightning strikes or by nitrogen-fixing
bacteria which changes nitrites into nitrates. Plants use those nitrates for proteins and DNA.
Humans consume plants directly or they consume animals that have consumed those plants.
15. List the 4 Canadian biomes and briefly describe each one.
(There are five major biomes; you will be required to provide information on 4)
Tundra – low temperatures, short growing season, low precipitation
Boreal Forest – harsh climate, changeable weather temperature extremes
Temperate Deciduous Forest – long growing season, higher temperatures, faster decomposition
Grassland – longer growing season, higher temperatures, rich fertile soil
Mountain Forest – temperatures vary with elevation, windy, heavy precipitation, fast flowing
rivers
16. Explain the differences between a freshwater ecosystem and a marine ecosystem.
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Fresh Water
Covers 3% of earth’s surface
Less than 1% salt concentration
Consist of rivers and lakes
Watersheds
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Marine
Covers 70% of earth’s surface
3% salt concentration
Most evaporated water comes from oceans
Contains coral reefs, estuaries, and
mangroves
17. Create a table listing the advantages and disadvantages of using pesticides.
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Advantages
Control unwanted pests
Increase food yields
Increase profits
Better looking species (lawn)
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Disadvantages
Bioaccumulation
Killing innocent bystanders
Pollution
Resistance