BIOL 1000 Chapter Notes -Circadian Clock, Melanin, Nightlight
Document Summary
Light serves as two important functions for life on earth: first, it is a source of energy that directly or indirectly sustains virtually all organisms, second, light provides organisms with information about the physical world that surrounds them. Sun converts over 4 million tonnes of matter into energy every second. This energy is given off as electromagnetic radiation, which travels in the form of a wave at a speed of 1 079 252 848km/h (speed of light) The wavelength of electro- magnetic radiation ranges from less than one picometre (10-12 m) for cosmic rays to more than a kilometre (106m) for radio waves. Light is commonly defined as the portion of the electromagnetic spectrum that humans can detect with their eyes. 1. 1 b light interacts with matter light has no mass, it is still able to interact with matter and cause change. This change is what allows the energy of light to be used by living things.
