Problem:

Question: Imagine that a cell within a tissue is expressing a protein that leaves the cell and can "signal" to other cells. Which cells are likely to respond to the signal?

A) Cells that are within range of the signaling molecule and are the same type of cell

B) Cells that are within range of the signaling molecule and have protein receptors that binds the signaling molecule

C) Cells that are within range of the signaling molecule and are expressing their own signaling molecules

D) Cells that are within range of the signaling molecule

Give reasoning with your answer.