The process by which green plants make large organic molecules (glucose) from small inorganic molecules, carbon dioxide and water using light energy which is absorbed by chlorophyll. The by-product of photosynthesis is oxygen.
How do green plants obtain raw materials for photosynthesis?
- Carbon dioxide diffuse through the stomata
Plants obtain CO2 from the air. Only about 0.04% of the air is CO2. Therefore, the leaves must be very efficient in absorbing it. The leaf is held out into the air by the stem and leaf stalk and its large surface area helps to expose it to as much air as possible. CO2 diffuse into the air spaces through the stomata. It dissolves in the film of moisture around the cell wall of the mesophyll cells. It can then diffuse through the cell wall and cell membrane of each cell into the chloroplast down a concentration gradient.
- water is absorbed from the soil by the root hair cells
Water is absorbed from the soil by the root hair cell by osmosis