Not "what", "water"

And Bill is an enzyme, while I am water...
You are water. You're not really organic; you're
neither acidic nor basic, yet you're an acid
and a base at the same time. You're strong
willed and opinionated, but relaxed and ready
to flow. So while you often seem worthless,
without you, everything would just not work.
People should definitely drink more of you
every day.

Which Biological Molecule Are You?
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