Since chloroplast use energy to make food for plant cells (Photosynthesis) I could compare it to lunch money, and how you have to keep refilling up, and up, just to use it again for food, for yourself.
The answer is because biology is easy and they're known around the world.
Because tropical levels used to be broken because temperatures hasn't varied in the years and history of global temperatures and history.
The smallest particle of any type of matter would be an Atom
