1. A2 OCR Biology
UNIT 2 – Module 3
Ecosystems – Revision Quiz
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2. 1. Define the term population (1)
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2. Define the term community (1)
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3. What term would you use to define the role each species plays in
an ecosystem? (1)
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4. List three abiotic factors that can affect an ecosystem (2)
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5. What type of organisms feed on waste material or dead
organisms? (1)
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6. What term describes the level at which an organism feeds in a
food chain? (1)
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7. Where does all the energy in a food chain initially come from? (1)
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3. 8. Name three types of pyramid that can be used to represent a food
chain (3)
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9. What units do you use for productivity? (1)
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10.Define the term Net Primary Productivity (2)
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11.Give three ways to improve primary productivity? (3)
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12.Give two ways of improving secondary productivity? (2)
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13.Define the term succession (1)
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4. 14.What term is used to describe the species that first colonise a new
habitat? (1)
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15.What term is used to describe the final stage of succession? (1)
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16.Name three plants that are involved in sand dune succession (3)
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17.What is a saprotroph (1)
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18.What is the name of the nitrogen fixing bacteria that live in root
nodules? (1)
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19.What type of relationship do they have with the plant? (1)
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20.What type of bacteria cause nitrification? (1)
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21.What process is it when the ammonium gets converted to
nitrites? (1)
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5. 22.Define the term carrying capacity (2)
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23.Name two techniques used to manage small scale timber
production (2)
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24.What type of organisms tend to adopt the r-strategy for
population growth?(1)
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25.What happens at the log phase of population growth (2)
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26.Define the term intraspecific competition (1)
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27.What idea did Gause form about interspecific competition (1)
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6. 28.What are the three principals for managing large scale timber
production (3)
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29.Give three examples of management strategies used in
conservation (3)
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30.Give two ways the human population has threatened biodiversity
(2)
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31.Give the three species introduced by humans to the Galapagos
islands (3)
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END OF TEST