Meaning of photosynthesis
Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll and other pigments in their cells. The process converts carbon dioxide and water into organic compounds, such as glucose and releases oxygen as a by-product. Photosynthesis is an important source of oxygen and food for most living organisms on Earth.
Photosynthesis is the process by which green plants, algae, and some bacteria convert sunlight, carbon dioxide, and water into glucose (a simple sugar) and oxygen. It is an essential process for life on Earth as it produces food and oxygen necessary for other organisms to survive. Here are the steps involved in photosynthesis:
1. Absorption of sunlight: The process of photosynthesis begins when chlorophyll, a green pigment found in the chloroplasts of plant cells, absorbs sunlight.
2. Conversion of light energy: The absorbed sunlight is converted into chemical energy in the form of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate), which are energy carriers.
3. Splitting of water molecules: Water molecules from the plant's roots are transported to the chloroplasts. In a process called photolysis, the water molecules are split into hydrogen ions (H+), electrons (e-), and oxygen molecules (O2).
4. Production of ATP and NADPH: The energy from the absorbed sunlight is used to produce ATP and NADPH. These energy carriers will be utilized in the next step.
5. Carbon dioxide fixation: Carbon dioxide gas from the environment enters the plant through tiny pores called stomata on the leaves. In the chloroplasts, carbon dioxide combines with the hydrogen ions and electrons from the previous step to form glucose (C6H12O6).
6. Release of oxygen: As a byproduct of the photosynthesis process, oxygen molecules (O2) are released into the atmosphere through the stomata.
7. Storage of glucose: Glucose produced during photosynthesis can be used immediately for energy metabolism by the plant or stored as starch for future use.
Overall, photosynthesis is a complex series of chemical reactions that convert sunlight into chemical energy, capture carbon dioxide from the atmosphere, and produce glucose as a source of energy for the plant.