Q: Food chains and what describe the transfer of energy within an ecosystem, from one organism to another?   A:
food webs
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Q: What is the basis of enzyme classification?   A:
reactions they catalyze
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Q: Pavement cells, large, irregularly shaped parenchymal cells which lack chloroplasts, make up the majority of what?   A:
epidermis
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Q: What cannot exist between energy levels?   A:

electrons
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