Describe how the discovery of the electron led to the plum pudding model.

Within The development of the model of the atom, this learning objective asks you to describe how the discovery of the electron led to the plum pudding model. Focus on the approved ideas plum pudding model and connect them clearly to Atoms and isotopes. A strong response should state the relevant particle, radiation, isotope, decay, half-life or nuclear-equation idea, then explain how it answers the exact command word. Avoid swapping nearby concepts such as atomic number and mass number, isotope and ion, alpha, beta and gamma radiation, or contamination and irradiation.