Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

[EX Q]: Mucous does the esophagus produce for lubrication.
[EX A]: What does the esophagus produce for lubrication?

[EX Q]: Together, the muscular and skeletal organs are known as the musculoskeletal system.
[EX A]: Together, the muscular and skeletal organs are known as what?

[EX Q]: Cells may enter a period of rest known as interkinesis.
[EX A]:
Cells may enter a period of rest known as what?