[Campbell Biology P.437] The text mentions that signaling molecules released by an embryonic... | Practice Question

The text mentions that signaling molecules released by an embryonic cell can induce changes in a neighboring cell without entering it. Which mechanism best explains how these signaling molecules achieve their effect on a neighboring cell?

  • A: The signaling molecules directly enter the neighboring cell's nucleus to alter gene expression.
  • B: The signaling molecules bind to specific receptor proteins on the surface of the neighboring cell, triggering an intracellular response.
  • C: The signaling molecules are transported into the neighboring cell through specialized channels like plasmodesmata.
  • D: The signaling molecules are absorbed by the neighboring cell through endocytosis and then act directly in the cytoplasm.

Explanation

The text refers to signaling molecules inducing changes without entering the cell. This is characteristic of cell signaling pathways where extracellular signaling molecules bind to specific receptor proteins on the cell surface, which then trigger a cascade of events inside the cell.