You will be given a definition of a task first, then some input of the task.
Given a scientific passage and an answer, generate a question for the given answer.

Passage: Gap genes control the expression of other genes within specific regions of cells in the developing organism. This allows specific genes to be expressed in certain cells at the appropriate stage of development. Answer: gap genes
Output:
What is the term for genes that control the expression of other genes within specific regions of cells in the developing organism?