The Drosophila regulatory segment that defines the location of Eve stripe 2 contains binding sites for four different transcription regulators: two repressors (Giant and Krüppel) and two activators (Bicoid and Hunchback). For Eve to be efficiently expressed in stripe 2, both repressors must be absent and both activators present. What would you expect to see in flies that lack the gene that encodes Bicoid? (Assume that Bicoid does not influence the expression of Hunchback, Giant, or Krüppel.)
A. Stripe 2 would become narrower.
B. All 7 stripes would disappear.
C. Stripe 2 would become fainter.
D. Stripe 2 would expand toward the tail of the embryo.
E. Stripe 2 would expand toward the head of the embryo.
Ans: C. Stripe 2 would become fainter.
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