Intake of Water and Carbon dioxide:

Water and carbon dioxide are the raw materials of photosynthesis. The plants have elaborate mechanisms for the intake and transport of these raw materials.

Intake of Water by root hairs:

Water and salts are absorbed by the roots and roots hairs which provide the larger surface areas for this absorption. The sap present in the root hairs is more concentrated (contains more salts) as compared to the dilute solution (containing fewer salts) present in the surrounding soil. Thus, water enters from the soil into the root hairs by osmosis thus diluting their sap as compared to the inner cells of the root. In this way, water enters the inner cells of the root and eventually reaches xylem vessels. The xylem vessels transport water to the leaves using the force of transpiration pull.

Intake of Carbon dioxide into the mesophyll cells:

The air that enters the leaf through tiny pores (stomata) diffuses into the air spaces present around mesophyll cells. This air carries CO₂, which gets absorbed in the thin layer of water surrounding the mesophyll cells. From here the carbon dioxide diffuses into the mesophyll cells.