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

[Q]: The ileocecal valve, a sphincter, is usually in a constricted state, but when motility in the ileum increases, this sphincter relaxes, allowing food residue to enter the first portion of large intestine.
[A]: The ileocecal valve, a sphincter, is usually in a constricted state, but when motility in the ileum increases, this sphincter relaxes, allowing food residue to enter the first portion of what?


[Q]: Microevolution is the process by which organisms change in small ways over time.
[A]: What is the process by which organisms change in small ways over time?


[Q]: The name of positive ion ion always comes first.
[A]:
The name of which ion always comes first?