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]: Yeast fermentation causes holes in bread.
[A]: What causes holes in bread?


[Q]: A(n) organ is a structure that is composed of one or more types of tissues.
[A]:
What is a structure that is composed of one or more types of tissues?