Biodiversity Review Sheet
A. Use the following food web to answer the questions:
1. Name a producer - _____green plant___________________________
2. Name the primary consumers - ___ rabbit, goat, insect_____________
3. Name the secondary consumers - ___jackal, mouse __
4. Name the tertiary consumers - ___wild cat, owl, snake______________
5. Name the quaternary consumers - ____lion, hawk___________________
6. Name the level for the lion - ___quaternary consumer___________________
7. How many primary consumers are on the web? - _____3______________
8. How many secondary consumers are on the web? - ___2_______________
9. How much energy is passed from the rabbit to the wild cat? _10_% How much energy is lost from the rabbit to the wild cat? 90%
10. Consider your response to #9 when responding: Which has more energy-the plant or the goat? _Plant. Organisms lower on the food
chain have higher energy since energy is lost when you move up each level._
11. Would you expect to find more of the rabbit or the jackal? Explain. - _rabbit – lower on the food chain so more of them to supply
food for next level__
12. Who has more available energy, the mouse or the wild cat? Explain. - __mouse – always more energy at the lower level because they
don’t use as much energy for live processes_
13. Who would have greater biomass, the rabbit or the lion? Explain. - _rabbit – always more biomass at the lower level because there are
more organisms at the lower level__
14. If the number of rabbits decreased, would the number of wild cats increase or decrease? Explain. - _Decrease by a quite a bit. Wild
cats only have one other source of food.___________________________
15. If the hawk population became high, would the number of mice increase or decrease? Explain. - _Increase. More hawks means more
snakes being eaten which means the mice population could start increasing__
16. What is a herbivore? __eats plants____________________ Give examples from the diagram - _goat, rabbit __________
17. What is a carnivore? __eats meat_____________________ Give examples from the diagram - jackal, lion, wild cat, owl, snake, hawk
18. Name the omnivores in the diagram - _______mouse____________________
19. Name the top carnivore (s) in the diagram - ____lion, hawk, owl____
20. What is an autotroph? __makes its own food___________
Give examples from the diagram - ____green plant ___________
21. What is a heterotroph? _gets its food from another source_ Give examples from the diagram - _ goat, rabbit, mouse, jackal, lion, wild
cat, owl, snake, hawk _________________________
22. If the green plant were sprayed with pesticide, explain what the pesticide level would be like in the mouse, the snake and the hawk.
What is this called? What is the difference between pesticides such as DDT and newer pesticides?
If the green plant were sprayed with pesticide, the pesticide level would be fairly low in the mouse but would be higher in the snake
and even higher in the hawk. This is called bio amplification – the amount of pesticide is amplified (increased) as you go up each
trophic level. DDT is soluble in fat so it stays in your body. Newer pesticides are soluble in water so you can “pee” them out.
23. Would the mouse be considered a pest in this ecosystem? Explain.
The mouse would not be considered a pest. A pest is something humans think is annoying. The mouse has an important place in this
food web.
24. List the food chains from the food web above ending with the lion (6in total).
Plant  goat  lion
Plant  rabbit  jackal  lion
Plant  goat  jackal  lion
Plant  rabbit  wildcat  lion
Plant  mouse  wildcat  lion
Plant  insect  mouse  wild cat  lion
25. Complete and label the food pyramid below for the food web above. Place each organism in its highest level possible.
B. Additional Questions:
1. Would the above ecosystem be an open population or a closed population? Explain.
The above ecosystem would be OPEN. Organisms would be free to enter and leave at will.
2. What is an organism’s ecological niche? What is an organisms’ habitat?
Ecological niche is an organism’s ‘place’ or ‘role’ within an ecosystem. Habitat is an ecological or environmental area that is
inhabited by a particular species of animal, plant or other type of organism.
3. What is an exotic species? What kind of problems can be created when an exotic species is introduced into an ecosystem?
An exotic species is a non-native species that is introduced into an ecosystem. When an exotic species in introduced into an
ecosystem, it can cause problems because: it competes with native species for food, habitat; may compete for the same
‘niche’; may change the balance of the ecosystem; may not have natural predators (overpopulation); we cannot predict what
effects the introduction of new species can have
4. What is an ecological footprint? Why is it important?
Ecological footprint is a measure of an individual's or a population's impact on the environment
5. What is the meaning of extinct? Endangered?
A species that is no longer found anywhere on Earth is extinct.
A species that is close to extinction in all parts of Canada or in a significantly large location is endangered.
6. What is the population growth equation? What do the following terms mean: Natality? Mortality? Immigration?
Emigration? R = (Natality + Immigration) – (Mortality + Emigration). Natality – organisms being born; Mortality –
organisms dying; Immigration – organisms moving into an area; Emigration - moving out of an area
7. What is exponential growth? Linear growth?
Exponential growth – doubling; very rapid growth. Linear growth – steady growth
8. What do the following terms mean: Biotic potential – max number of offspring a species could produce if resources were
unlimited (species imposes on itself so don’t all die off); Carrying Capacity - The maximum number of individuals of a
species that can be supported indefinitely by an ecosystem; Limiting factor - anything that prevents a population from
attaining biotic potential; Which of the following is least likely to be a limiting factor in a meadow? Space, food, oxygen.
Give an example of a limiting factor - Which of the following would be density-dependent factors? Space, disease, fire,
food, water, weather. (density-dependent factors increase in significance as a population grows (disease due to overcrowding,
lack of resources, space)). Which of the following would be density-independent factors? Space, disease, fire, food, water,
weather. (density-independent factors does not depend on the population size (fire, weather))
9. What is the carbon cycle? The process by which carbon is cycled through the environment. How have humans impacted it?
We have cut down trees and we’ve released too much carbon dioxide through burning of fossil fuels (burning gasoline in
cars, factories, power plants (coal)), forest fires. What is photosynthesis? Photosynthesis is the process by which green plants
and other producers use energy from the sun, and carbon dioxide and water to produce sugars and oxygen.
6 CO2 + 6 H2O
+ light  sugar (C6H12O) + 6 O2 Cellular respiration is the process by which most living
things generate useful energy by combining oxygen and sugars to produce carbon dioxide and water.
sugar (C6H12O) + 6 O2  6 CO2 + 6 H2O
10. What is the difference between a population, a community and an ecosystem?
All of the members of the same species, living in the same habitat at the same time are referred to as a population.
The collections of all the populations of all the species in a particular area is called a community.
An ecosystem is made up of the living and non-living components of a biological community and their interrelationships
11. Why are frogs good indicators of ecological damage? Why could it cause problems if frogs (or any organism) were
eliminated from an ecosystem? (Read text p.10-12)
Frogs need good habitat, good air quality, they’re susceptible to UV radiation and to climate change.
12. What is the purpose of fertilizers? Why can this cause a problem? (What kind of a cycle does it initiate?)
Fertilizers restore nutrients and increase production from land. Fertilizers can run off into lakes, along with decaying plant
matter, causing an algal bloom.
13. What is the difference between abiotic and biotic? Biotic – living. Abiotic – non-living
14. List one way how humans negatively affect each of the biogeochemical cycles we learned about in class.
Water – pollution (factories)  acid rain
Carbon – burning fossil fuels; mining, forestry
Nitrogen – crop removal, adding fertilizers, burning fossil fuels
Phosphorus – crop removal, adding fertilizers
15. How do legume plants and bacteria help each other?
Legume plants provide bacteria with sugar
- Bacteria provide plants with usable nitrogen
16. How can over-fertilizing crops affect organisms in aquatic ecosystems?
It makes algae die. Decomposing bacteria use up the oxygen in the water, choking out fish and other animals.
- Also, nitrates can attach to the hemoglobin in blood cells, reducing the ability to carry oxygen to body tissues.
17. Why has the amount of carbon dioxide in the atmosphere increased in recent years?
- people have been cutting down trees
- people have been mining for metals and minerals
- people have been burning fossil fuels
18. Why can greenhouse gases affect Earth’s climate?
- The CO₂ gets stuck in the atmosphere, and it keeps some heat from escaping the Earth. This is how the Earth heats up.
19. What is the difference between weather and climate? Be able to recognize examples of each.
- Weather – change in atmospheric events that occur each day
Eg. It’s 15°C and windy
- Climate – the average weather in a certain place over many years
Eg. Saskatchewan has cold winters and warm summers
20. Explain how humans depend on the greenhouse effect to survive and yet, by contributing more greenhouse gases to our
environment, the greenhouse effect is harming us.
- Greenhouse gases trap the sun’s energy on Earth, keeping us warm and allowing us to survive. Adding more gases is
making the Earth too warm and damaging our planet.