How do the reactant molecules of photosynthesis reach the chloroplasts in leaves?
Stomata and xylem
So the reactants of photosynthesis are water, carbon dioxide and light energy.
The water reaches the leaves via the xylem, which is found in the vascular bundle which is made of 2 main parts, the xylem (which carries water from the roots up the plant) and the phloem (which carries sugar from the leaves to the rest of the plant). Basically the roots absorb the water and transports it up the xylem, which gets it to the leaves.
Carbon dioxide reaches the chloroplasts in the leaves via a stomata. It basically is a microscopic mouth found on the underside of leaves that is responsible for releasing water (transpiration) in the form of dew, and gas exchange. It takes in carbon dioxide and releases oxygen once the photosynthesis reaction is complete.