Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: The biological electron transport chain provides for an orderly, stepwise transfer of electrons. Both NADH (reduced nicotinamide adenine dinucleotide) and FADH2 (reduced flavin adenine dinucleotide) are energyrich molecules that liberate a large amount of energy during oxidation. Free energy released during the transfer of electrons from either of these molecules to oxygen drives the synthesis of ATP (adenosine triphosphate) formed during respiratory metabolism. The reactions are as follows:. Answer: oxidation

A: The biological electron transport chain provides for an orderly, stepwise transfer of electrons. both nadh (reduced nicotinamide adenine dinucleotide) and fadh2 (reduced flavin adenine dinucleotide) are energy rich molecules that liberate a large amount of energy during what?
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Q: Passage: Most fungi get organic compounds from dead organisms. Fungi use their hyphae to penetrate deep into decaying organic matter. They produce enzymes at the tips of their hyphae. The enzymes digest the organic matter so the fungal cells can absorb it. Fungi are the main decomposers in forests. They are the only decomposers that can break down cellulose and wood. They have special enzymes for this purpose. Answer: hyphae

A: What do fungi use to penetrate deep into decaying matter?
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Q: Passage: Fertilization joins two haploid gametes into a diploid zygote. Answer: fertilization

A:
What process joins two haploid gametes into a diploid zygote?
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