(mÄth'Än') A colorless, odorless, flammable gas that is the simplest hydrocarbon. It is the major constituent of natural gas and is released during the decomposition of plant or other organic compounds, as in marshes and coal mines. Methane is the first member of the alkane series.
In photosynthesis, solar energy is converted to chemical energy. The chemical energy is stored in the form of glucose (sugar). Carbon dioxide, water, and sunlight are used to produce glucose, oxygen, and water.
Energy from sunlight, water absorbed by the roots, and carbon dioxide from the atmosphere produce glucose and oxygen by photosynthesis. Photosynthesis is the process by which plants and other things make food. It is a chemical process that uses sunlight to turn carbon dioxide into sugars the cell can use as energy. As well as plants, many kinds of algae, protists and bacteria use it to get food. Photosynthesis is very important for life on Earth.