[Campbell Biology P.1106] Based on the text and your biological knowledge, what would most li... | Practice Question

Based on the text and your biological knowledge, what would most likely happen if, just before neural tube formation, frog embryos were treated with a drug that enters all cells and blocks the function of microfilaments?

  • A: The neural tube would form normally, but the embryo's subsequent growth would be inhibited.
  • B: The neural tube would fail to form properly, as microfilaments are essential for the cell shape changes required for invagination and tube closure.
  • C: The embryo's cells would undergo excessive apoptosis, preventing neural tube formation.
  • D: Cell division would cease, leading to immediate embryo death before neural tube formation could begin.

Explanation

Neural tube formation is a complex morphogenetic process involving cell shape changes, cell migration, and tissue invagination. Microfilaments, composed of actin, are crucial for these cellular movements and changes in cell shape, particularly the apical constriction that drives invagination. Blocking their function would prevent the cells from undergoing the necessary shape changes to form and close the neural tube, as suggested by Concept Check 47.2, question 2.