When the Bicoid protein is expressed in Drosophila, the embryo is still syncytial (divisions between cells are not yet fully developed). This information helps to explain which observation by Nüsslein-Volhard and Wieschaus?
A) mRNA from the egg is translated into the Bicoid protein.
B) Bicoid protein diffuses throughout the embryo in a concentration gradient.
C) Bicoid protein serves as a transcription regulator.
D) Bicoid protein determines the dorsoventral axis of the embryo.

Question

Quizplus · Accepted Answer

The fact that a syncytial embryo still responds to the Bicoid protein suggests that it is diffusing throughout the embryo in a concentration gradient, rather than working through regulated transcription or cell-cell signaling, as these mechanisms would likely require the presence of fully developed cell divisions.

When the Bicoid Protein Is Expressed in Drosophila, the Embryo