In the reactants there is a curvy arrow, what does the direction of the arrow indicate?

Organic-

There are four major classes of biological macromolecules (carbohydrates, lipids, proteins, and nucleic acids); each is an important cell component and performs a wide array of functions.

Inorganic-

Water. perhaps most important and most abundant. molecule in the body; electrolytes (ions) molecules that tend to disperse in solution into charged atoms; gasses; carbohydrates.

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