The embryo, endosperm and seed coat.
It provides energy for the cell to build, repair, and reproduce. Cells needing more energy have more mitochondria.
Electricity could be discovered using batteries based on zinc or lead, but without copper wiring it would remain little more than a scientific curiosity. Electric motors and generators require large amount of wiring, so they are impossible to build on large scale in this world
The Answer IS AEROBIC RESPIRARTION because it’s The breakdown of food to create energy in the presence of oxygen.