This study is devoted to thermogravitational convection of pseudoplastic nanofluid in the cavity. The lower wall of the cavity is heat-conducting and a local heater placed on this solid wall has a constant volumetric heat generation. The cavity is filled with a mixture of carboxymethyl cellulose with water and tiny solid particles of copper oxide. The problem is described by unsteady Oberbeck-Boussinesq equations with non-primitive variables such as stream function and vorticity. In the course of the study, the influence of the volume fraction of solid nanoparticles, the height of the heat-conducting lower wall on nanofluid flow and heat transfer was analyzed.