for the common emitter configuration,the physics is the same but the I-V characteristics look different because Ic is plotted versus Vce with the varying parameter Ib,If forward biasing the base-emitter junction,electrons will be injected from the emitter into the base and hole from the base into the emitter.The injected holes recombine in the emitter or at the emitter contact and flow out the common emiter contact,but a small fraction of the electrons injiected into the base will recombine and flow out the base contact.Most of the elections diffuse across the thin base to be collected by    the collector.