page 06 8. The diagram shows events in the response to light in the rod cells of animals. outer membrane of rod cell inside of rod cell photoactivated rhodopsin activation of X by rhodopsin channel protein Z broken down by Y activation of Y by X X Y X Z Z When a photon of light hits a molecule of rhodopsin it activates molecule X, which disassociates from rhodopsin and activates another molecule, Y. Activated Y breaks down molecule Z, which in turn affects the function of a channel protein. Which row in the table identifies molecules X, Y and Z? Molecule X Molecule Y Molecule Z A cGMP transducin PDE B transducin PDE cGMP C PDE transducin cGMP D transducin cGMP PDE