instruction:
Given a scientific passage and an answer, generate a question for the given answer.
question:
Passage: In many ways, humans are unique among mammals. For example, we have bigger brains and a greater ability to learn than any other species in the mammalian class. In many ways, however, we are typical of the mammalian order to which we belong. That order is the Primate Order. To fully understand what it means to be human, you need to know more about this fascinating order of mammals. Answer: humans
answer:
What mammalian class has the greatest ability to learn?

question:
Passage: A solute generally lowers the freezing point of a solvent, which is called freezing point depression. For example, spreading salt on an icy road melts the ice. Answer: lowers it
answer:
A solute generally does what to the freezing point of a solvent?

question:
Passage: Enzymes are involved in most biochemical reactions, and they do their job extremely well. A typical biochemical reaction could take several days to occur without an enzyme. With the proper enzyme, the same reaction can occur in just a split second! Without enzymes to speed up biochemical reactions, most organisms could not survive. The activities of enzymes depend on the temperature, ionic conditions, and the pH of the surroundings. Some enzymes work best at acidic pHs, while others work best in neutral environments. Answer: enzymes
answer:
Most organisms could not survive without what being present to speed up biochemical reactions?