Answer:
Present:
Oxygen within the air will cause sliced fruit to brown, a method referred to as enzymic browning (an oxidation reaction). Phenols and the enzyme phenolase are found in the cells of the apple, and when these are exposed to oxygen in the air, for example through slicing, the oxygen causes a reaction.
Absent:
If there is no oxygen anymore respiration will stop and decay of the fruit will start. absence of oxygen can cause fermentation to occur which will produce strong off flavours.
Explanation:
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