The word photosynthesis is derived from Greek and is a combination of two words (Photo: light; Synthesis: to combine). Photosynthesis is the conversion of light energy into chemical energy by living organisms. The raw materials required for photosynthesis are carbon dioxide and water; the energy source is sunlight (chlorophyll in plants help to trap sunlight) and the end-products are oxygen and (energy rich) carbohydrates, for example sucrose, glucose and starch. This process is arguably the most important biochemical pathway,^[1] (most important) since nearly all life on Earth either directly or indirectly depends on photosynthesis because no life form on earth can live without oxygen (the major product of photosynthesis).

The leaf is the primary site of photosynthesis in plants.

Sunlight: Plants absorb light primarily using the pigment chlorophyll                                  that is green in colour, which is the reason that most plants have a green colour.

Carbon Dioxide: Carbon dioxide is taken in directly from the    atmosphere by tiny pores on leaves called stomata.

Nitrogen: nitrogen is present in abundance in the atmosphere but                Leaves cannot pick up nitrogen from the atmosphere directly.                They pick up nitrogen in the soluble form with water through roots. Special bacteria called rizobium convert atmospheric nitrogen into soluble form.

Water: water is picked up by the roots from the soil.

1. Oxygen- Oxygen is given out during the process of photosynthesis through the tiny pores called stomata.

2. Carbohydrates- Energy rich carbohydrates such as sucrose, glucose and starch are the other products of the process.