Growth Factors and Tyrosine Kinase Receptors -- MAP Kinases Pathway -- Phosphatidylinositol 3-Kinase Pathway -- Cytokine Pathway -- TGFβ Pathway -- G-proteins-coupled Receptors -- Wnt Pathway -- Notch Pathway -- Hedgehog Pathway -- Integrins -- Semaphorins and Adhesion Molecules -- Toll-like Receptors, Interleukin 1 (IL1) and NFκB -- Lymphocyte Receptors Pathways -- Nuclear Receptors Pathways -- Ion Channels-coupled Receptors -- Signalling by Oxygen and Nitric Oxide -- Cell Cycle Control -- Apoptosis Induction and Regulation.