Plants, using the energy of the sun, manufacture carbon-based organic molecules, and these molecules are incorporated and then transformed into the bodies of other living things, including human beings. Plants get their carbon from the air. The inorganic CO2 (carbon dioxide) in the atmosphere is used by plants in a process called photosynthesis. This is the "machine" in plants that takes inorganic CO2 from the atmosphere and changes it to organic C (carbon) in plants. The agent for capturing and storing solar energy in the form of molecular bonds is chlorophyll.

A portion of the trapped solar energy is used in the process of bonding the atoms together to make the carbohydrate or simple sugar molecules. That energy is "stored" in the bonds themselves, and can be released by other chemical processes. Those bonds can be thought of as an energy-storage mechanism, somewhat like a battery. These relatively simple organic molecules--carbohydrates--produced by photosynthesis provide the reservoir of energy on which all life forms draw. For example, we "burn" plant-produced carbohydrates to power all our physical activities.

H2O molecules pass into the leaf from the soil, through tiny root hairs on the root and up into the plant and leaves, where water is broken down and combined with the atoms of CO2, which is absorbed from the atmosphere. The energy of sunlight is captured in the chlorophyll in the green chloroplasts in cells of leaves. Plants appear green to us, in fact, because of their role in capturing the sun's energy: plants are photosynthetically "blind" to green light. They absorb the blue and red spectrum but reflect the green spectrum. The red and blue light from the sun powers the breakdown of H2O (water) molecules, forming oxygen. In a second process, the so-called "dark phase," CO2 (carbon dioxide) is reduced to its constituent atoms and the carbon, hydrogen, and oxygen are converted into simple carbohydrates such as glucose (CH2O)6.

Oxygen--crucial for our own life--is released as a by-product of the process.

To repeat: the sun is the power plant that drives this biochemical factory. The enormous power of the sun, captured and subtly transformed by biological processes, is the power that lifts your arms to the keys and moves your eyes along a line of text.