Given a scientific question, generate a correct answer to it.

Ex Input:
From what do tubeworms found deep in the galapagos rift get their energy from?

Ex Output:
chemosynthetic bacteria

Ex Input:
What works by providing a lower energy pathway from reactants to products?

Ex Output:
catalyst

Ex Input:
In flowering plants, male gametophytes are in grains of what?

Ex Output:
pollen