But these functions of the living take place in such a tiny factory, it boggles the mind. One square millimeter at the middle of a leaf has 500,000 chloroplasts. It is difficult to picture one square millimeter. However, one can easily picture the size of a penny. See the activity at the end of this article for further instructions.
Pigment is a very complex project.
The chlorophyll pigment molecule is anchored by a long chain made of carbon and hydrogen in a structure called the thylakoid of a plant. The chlorophyll will not work unless it is anchored in this thylakoid. The chlorophyll pigment molecules are not placed randomly. They are organized in highly efficient assemblies from 250 to 400 each called photosystems . All of the pigment molecules within a photosystem are capable of absorbing photons, but only one chlorophyll molecule per photosystem actually uses the energy in the photochemical reaction.