Photosynthesis is the process through which green plants and other specific living organisms utilize light energy to convert water and carbon dioxide in to simple sugars. Through photosynthesis, green plants are able to manufacture their own food which is essential for their growth. Most importantly, photosynthesis process releases oxygen as a by-product which is required by most organisms for respiratory. Photosynthesis occurs in the chloroplast cells in the green plants. Chloroplasts contain green pigment referred to as chlorophyll which absorbs light energy from the sun. `
Photosynthesis involves two significant stages. The initial stage reactions are highly dependent on light energy and thus referred to as light stage. In light stage, light energy splits water molecules into oxygen and hydrogen ions. Oxygen gas is released to the air as a by-product. The hydrogen ions are moved to the next stage of photosynthesis.
The second stage light independent reaction and thus referred to as dark stage. In dark stage, carbon dioxide is transformed into simple sugars referred to as Adenosine Tri-Phosphate (ATP) in the presence of hydrogen ions through a process known as carbon fixation. Carbon fixation involves an endothermic chemical reaction and thus photosynthesis requires supply of energy to drive the process.
Significance of Photosynthesis
Photosynthesis takes place in green plants, algae, seaweeds and particular bacteria that contain green pigment. These living organisms serve as authentic factories for sugar, manufacturing millions of sugar molecules every second. These glucoses molecules are used as source of energy for the plant growth and reproduction. Glucose is also converted into cellulose by plants, and then used as cell wall in plant cells. Plants stores the excess glucose in form of carbohydrates and starch in stems, leaves and roots.
Animals do not manufacture their own food and therefore, animals ultimately depend on plants photosynthesis to acquire glucose needed for their growth. Animals depend on starch and carbohydrates stored in plant roots, leaves and stems for their living. Furthermore, the oxygen used by animals during respiration is produced during photosynthesis.
Additionally, the ancient photosynthesis products such as fossil fuels are used as a source of energy in modern world. The fossils such as coal, petroleum and natural gases involve the remains of ancient organisms which depended on photosynthesis many years ago. In fact, almost all life on this planet, indirectly or directly relies on photosynthesis as an energy, oxygen and food source, hence making photosynthesis among the most significant known biochemical processes.