[Mojave]

Then correct me - what non-respiratory chemical reactions in the human body do not require a liquid solution of some sort?

There's more to a human body than a liquid solution of some sort. That was easy.

Now it's your turn for a question. Why isn't all medical research simply done in vitro?

[DevNet]

You didn’t answer the question.

[UCANSEE2]

Why isn't all medical research simply done in vitro?

'Cause medical researchers can't breath under water.