HELP! AS Chemistry Ionisation energies

When looking at ionisation energy graphs. The first plotted point is the energy required to "rip off" the most outer electron of the atom (1st ionisation energy). Each point continues to increase due to factors of shielding, nucleus radius distance, and nucleus charge. Additionally, when you see the large jumps in required energy, this is due to the electron being taken from the next electron shell, which is closer to the nucleus and therefore will require much more energy.

Thanks, James.