Mixed convection in magnetohydrodynamic second grade nanofluid flow through a porous medium containing nanoparticles and gyrotactic microorganisms with chemical reaction is considered. Buongiorno's nanofluid model is used incorporating the buoyancy forces and Darcy-Forchheimer effect. Nanoparticles increase the thermal conduction in bioconvection flow and microorganisms simultaneously increase the stability of nanofluids. For the constructive (or generation) chemical reaction, the mass transfer displays an increasing behavior. Ordinary differential equations together with the boundary conditions are obtained through the similarity variables from the governing equations of the problem, which are solved by the Homotopy Analysis Method (HAM). The investigations are presented through graphs and the results are interpreted which depict the influences of all the embedded parameters,