Given a scientific passage and an answer, generate a question for the given answer.

[Q]: Passage: Cells are the tiny building blocks of living things. They couldn't be discovered until the microscope was invented. The discovery of cells led to the cell theory. This is one of the most important theories in life science. Answer: cells
[A]: What are all living things made of?

[Q]: Passage: Neutralization reactions between an acid and a base yield a salt and water. In some cases, this results in a completely neutral solution. However, some salts are weakly acidic or basic. How can we tell whether a given salt will act as an acid or base? Looking at the relative strengths of the acid and base that were used to form the salt can give us information on the acid-base properties of the resulting solution. Answer: neutralization
[A]: What kind of reactions between an acid and a base yield a salt and water?

[Q]: Passage: Figure 33.3 Apodemes are ingrowths on arthropod exoskeletons to which muscles attach. The apodemes on this crab leg are located above and below the fulcrum of the claw. Contraction of muscles attached to the apodemes pulls the claw closed. Answer: apodemes
[A]:
What are ingrowths on arthropod exoskeletons to which muscles attach?