The application of photosynthesis is a complex procedure requiring the presence of a number of different chemicals and energy sources. Chlorophyll-filled organelles, called chloroplasts, absorb sunlight, carbon dioxide and water, and convert this into ATP, or adenosine triphosphate (energy), and NADPH (coenzyme carriers of electrons). The plant then uses the ATP and the NADPH for its production of carbohydrates or sugar. The waste product from the process of photosynthesis is oxygen, which the plant releases into the atmosphere. Other organisms, humans included, use the oxygen released from the plant for their own energy production and, in turn, discharge carbon dioxide as a waste product. The plant absorbs this carbon dioxide and the process begins again.
The organelles that manufacture energy for the plant are called chloroplasts. The animal equivalent to chloroplasts are mitochondria. Mitochondria exist in every living cell, varying in shape, size and number depending on the type of the cell. Mitochondria absorb oxygen and convert it into ATP. That compound breaks apart, releasing energy and forming ADP, or adenosine diphosphate. ADP combines with another phosphate to become ATP, and the process of energy production continues. The cell of the animal uses the energy in much the same way as the cell of the plant, for life-sustaining processes.
The light we see is an electromagnetic radiation wavelength that is generated in 400 to 700 nanometers. When a photon (light measurement) of light is absorbed, the electron in the molecule that has absorbed the light becomes strengthened and is placed in an excited state. This excited state causes the molecule to decay, releasing the compound as light or heat, or for chemical work. For photosynthesis to occur, the light absorbed must be compatible with the electron energy source and the photon's level of excitability must be able to be transferred to a neighboring molecule.
Contained within the compartments of the cell are many flattened sacs called thylakoids. Held within the thylakoids are the pigments called lamallae that absorb the light. The absorption of light is based on its wavelength. The longer the wave, the more the potential energy. Violet, located at one end of the light spectrum, provides a long wavelength and, as a result, contains more energy then red, which is located at the other end of the spectrum. Red algae and certain bacteria use secondary pigments, called cartenoids, to increases their synthesis of energy by absorbing light waves at the red end of the spectrum. This is a survival mode, allowing the organisms to exist in areas of low light exposure or light that is refracted by surface water.