How Do Plants Store Energy During Photosynthesis?

Photosynthesis is the process plants and some algae use to convert light energy to chemical energy stored as sugar within chloroplasts — the energy factories found in plant cells. Plants need only carbon dioxide and water for photosynthesis to work. Chloroplasts are full of chlorophyll, a green pigment key to photosynthesis, which helps the plant absorb light. Energy stored during photosynthesis begins the flow of energy and carbon down the food chain.

The formula that describes photosynthesis is 6CO2 + 6H20 + light energy = C6H1206 + 602. What this chemical equation means is that photosynthesis combines light energy with six molecules of carbon dioxide and six molecules of water to produce six molecules of oxygen and one molecule of sugar.

Photosynthesis is divided into two main stages: light reaction and dark reaction. The light reaction converts light energy into adenosine triphosphate, the energy currency of all life, and Nicotinamide adenine dinucleotide phosphate, both of which become energy-carrier molecules needed for the dark stage or photosynthesis. This step occurs in the thyroidal membrane, a membrane found inside chloroplasts.

The dark reaction employs ATP and NADPH created in the light reaction to transform carbon dioxide into sugar. This phase happens within the plant's stoma in the dark. The main cycle in this stage is called the Calvin cycle, which consists of three stages. Stage one, also called carbon fixation phase, is when carbon dioxide combines with ribulose bisphosphate, a five-carbon sugar. In stage two, ATP helps convert the product of stage one into sugar. The third stage, or regeneration phase, again uses ATP to regenerate the reserve levels of RuBp in the cell, completing the cycle.

ATP is an essential component in the process of photosynthesis. Biologists consider it the currency of life, because it is cell's favorite source of energy to do just about anything, from moving muscles to enabling respiration.

Plants use light energy to start the photosynthesis process and fuel the storage of energy in sugars. Light is divided into various colors with their characteristic wavelengths with each wavelength represented by an individual pigment. Chlorophyll, a specific plant pigment, takes in blue and red light while carotenoid, another type of plant pigment, utilizes blue-green light waves. Green wavelengths are not absorbed efficiently by plants and is reflected by the plant's leaves and stems, which makes plants appear green.