Which of the following would most likely lead to the development of two heads in a Drosophila embryo, one at each end?
A) Injecting Nanos protein into the posterior region of the egg
B) Knocking out the expression of the bicoid gene in the anterior region of the egg
C) Knocking out the expression of the bicoid gene in the posterior region of the egg
D) Injecting the posterior region of the egg with cytoplasm from the anterior region of another wild-type egg.
E) injecting the anterior region of the egg with cytoplasm from the posterior region of another wild-type egg.

Question

Quizplus · Accepted Answer

Injecting the posterior region of the egg with cytoplasm from the anterior region of another wild-type egg would disrupt the normal gradient of morphogens that form along the anterior-posterior axis and could lead to the formation of two heads, one at each end. This is known as a "bicaudal" phenotype and has been observed in Drosophila embryos that have undergone this manipulation. The other options do not relate to disrupting the anterior-posterior axis and are unlikely to cause the development of two heads.

Which of the Following Would Most Likely Lead to the Development