Which layer or layers of the interior are believed to have convection cells?

Question

Quizplus · Accepted Answer

The mantle and outer core are believed to have convection cells. This is due to the heat generated by the inner core and the radioactive decay of minerals in the mantle causing the material to become less dense and rise to the surface, while cooler, denser material sinks back down in a continuous cycle. The inner core is too solid to have convection cells.

Which Layer or Layers of the Interior Are Believed to Have