Which Statement About Animal Development Is False?
A) Signaling Molecules $\beta$

question 19

Multiple Choice

Which statement about animal development is false?

• A) Signaling molecules interact to produce different combinations of signals that eventually guide embryonic cells to differentiate along different pathways.
• B) \(\beta\)-catenin is necessary but not sufficient for the formation of the primary embryonic organizer.
• C) Expression of embryonic genes usually begins just before gastrulation.
• D) The mouth of the sea urchin forms where the archenteron makes contact with the ectoderm.
• E) Cells can actively migrate during gastrulation.

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