Concept 11.1 Local Signaling Cells may communicate by direct contact Animal cells Gap junctions Cell junctions Plant cells Plasmodesmata between cell plants Signaling substances can pass freely between adjacent cells Cell?cell recognition Paracrine signaling Short distances One cell can secrete some chemical or molecule that can then act on neighboring cells Example growth factors Stimulate adjacent cells to grow and divide Synaptic signaling Nerve cells in brain from one cell to another mostly an electrical signal Electrical signal triggers release of neurotransmitter Long distance signaling Endocrine signaling Hormones travels in bloodstream Target cell specifically binds hormone 3 stages of cell signaling 1 reception signaling molecule will combine to receptor