試題詳解

14. What is a homeobox?
(A) a cluster of homeotic genes
(B)a sequence within a homeotic gene that encodes the DNA-binding portion of a transcription factor
(C)the portion of the promoter to which a homeoprotein binds to activate transcription of genes important for development
(D)an enhancer region needed for expression of a homeotic gene
(E) none of these are correct