Q: Given a scientific passage and an answer, generate a question for the given answer.
Passage: One way mucous membranes protect the body is by producing mucus. Mucus is a sticky, moist secretion that covers mucous membranes. The mucus traps pathogens and particles so they can't enter the body. Answer: mucus
A:
A sticky, moist secretion that covers mucous membranes is called what?