Why is nascent oxygen supposed to be toxic to aerobic life forms?

What is eutrophication?Explain its conseuences on the life of plants and animals living in such water. Why is oxygen depletion in a eutrophicated water body is faster at night than during the day?

The oxygen toxicity is related to:

Why is atmosphere essential for life ?

Why is anaerobic respiration less energy producing than aerobic respiration?

Why is water essential for life ?

Why is it not possible to define total life of radioactive substance?

Why the cyst is formed?

Why metabolism is considered as the defining feature of life forms?

Why is water essential for life?