Since Cells can have multiple cities (due to there size), The Important factor is the total number of population on that cell. Capturing a capital is therefore more beneficial than an empty cell with 0 population.
Effects 🚧
Depending on the number of population you have globaly in the game, diffrent bonuses can apply.
Capitals ☢️
Capuring a capital allow you to apply policies to the whole contry. These policies will have an effect on all the Cells of that contry even if you do now own them or if an ennemie play owns them.