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

The urea cycle, a set of biochemical reactions that produces urea from ammonium ions to prevent toxicity, occurs to some extent in the kidney, but primarily in what organ?
liver

Many adults and some children suffer from a deficiency of lactase. these individuals are said to be lactose intolerant because they cannot digest the lactose found in what?
milk

What term means the amount of a substance required to form a saturated solution in a given amount of solvent at a specified temperature?
solubility