In classical geometry, a point is an entity that has no extent.
In the modern set theoretic approach to topology, this is formalised as: a point in a spaceX is simply an element of the set X.
... not absorbed by the pigment molecules.
The typical overall chemical reaction of photosynthesis is:
6H2O + 6CO2 + light → C6H12O6 (glucose) + 6O2
In simple ...