[Campbell Biology P.264] According to Figure 11.4a and the associated text, how do signaling... | Practice Question

According to Figure 11.4a and the associated text, how do signaling substances typically pass between adjacent animal and plant cells through cell junctions?

  • A: They are actively transported across the plasma membrane into the neighboring cell.
  • B: They diffuse across the narrow extracellular space between the cells.
  • C: They are released into the bloodstream and travel to the target cell.
  • D: They pass directly through cytoplasmic connections between the cells.

Explanation

Figure 11.4a and the text explain that cell junctions gap junctions in animals, plasmodesmata in plants directly connect the cytoplasms of adjacent cells, allowing signaling substances dissolved in the cytosol to pass between them.