4T – Photosynthesis

Supporting article T: Explaining how Photosynthesis happens

http://library.thinkquest.org/06aug/02309/

Plants are unable to live without sunlight, it’s a fact! All the food that we eat, not to mention the fossil fuels we burn (petroleum etc.) are a product of photosynthesis. Photosynthesis is the process by which plants use the energy from sunlight to produce sugar, which is then converted into chemical forms of energy that can be used by biological systems.

The most commonly known types of photosynthesis are carried out by higher plants and algae, as well as by cyanobacteria and their relatives, which are responsible for a major part photosynthesis in oceans. These organisms convert carbon dioxide (CO2) into organic material through the reduction of this gas into carbohydrates. The initial energy for this process is provided by the light of the sun, which is absorbed by pigments like chlorophylls and carotenoids.

These chlorophylls absorb blue and red light, while the carotenoids absorb blue-green light. Green and yellow light are not absorbed by the photosynthetic pigments in plants, therefore, these light colors are reflected by or passed through the leaves. This is why plants are usually green.

The growth of plants and the length of time they remain active depend on the amount of light they receive. Light intensity influences the   manufacture of plant food, stem length, leaf color, and flowering. A geranium grown in low light tends to be spindly and the leaves light green in color. A similar plant grown in very bright light would tend to be shorter, better branched, and have larger, dark green leaves.

Although you aren’t actually taking a bite out of the sun, you receive sustenance from plants that have used the sun’s energy to grow. In a way, you could say that the sun is a part of you!