Transport properties of high transition temperature(high-Tc)superconductors apparently demonstrate two distinct relaxation rates in the normal state. We proposethat this superficial inconsistence can be resolved with an effective carrier (quasiparticle) densityn almost linearin temperature T. Experimental evidence both for and against this explanation is analyzed and we concludethat this offers a clear yet promising scenario. Band structure calculation was utilized todetermine the Fermi surface topology of the cuprate superconductor versus doping. Theresults demonstrate that an electron-like portion of the Fermi surface exists in awide range of doping levels even for a p-type superconductor, exemplified byLa2−xSrxCuO4−δ (LSCO). Such electron-like segments have also been confirmed in recent photoemissionelectron spectroscopy. The Coulomb interaction between electron-like and hole-likequasiparticles then forms a bound state, similar to that of an exciton. As aresult the number of charge carriers upon cooling temperature is decreased. Aquantum mechanical calculation of scattering cross section demonstrates that aT2 relaxation rate is born out of an electron–hole collision process. Above the pseudogap temperatureT* the normalstate of high-Tc cuprates is close to a two-component Fermi liquid. It, however, assumes non-Fermi-liquid behaviorbelow T*.