And once the binding takes place, these two monomers associate with one another to form a dimer and that creates conformational changes in these two structures found in a cytoplasm. Now these two structures, and by the way, this is the EGF receptor these two structures actually contain tyrosine protein kinase domains. And once a conformational change takes place upon binding and the dimerization process, a cross phosphorylation takes place and the carboxyl terminal ends of this tail and this tail are phosphorylated by the active sides of these corresponding kinases. And once we form these phosphorylated residues, we have an important adaptor protein known as GRB Two that binds onto this section and that calls upon another protein known as SOS. And what SOS does is it binds an inactive small G protein known as Ras. When Ras binds unto this structure, there's a conformational change that takes place in the Ras protein and the GDP Guanosine diphosphate is expelled and the GTP Guanosine triphosphate moves into that pocket.