1 If living in an area with frequent thunderstorms, consider buying a lightning protector. 2  These cost between $35 and $55. 3  Keep in mind that an invisible fence doesn't keep other dogs, animals or people out of the yard. If living in an area with frequent thunderstorms, consider buying a lightning protector. 2  These cost between $35 and $55. 3  Keep in mind that an invisible fence doesn't keep other dogs, animals or people out of the yard.
Carbon is essential for the survival, growth and reproduction of living things. It is a finite resource that comes in different forms and transfers from living to non-living things in various ways. Carbon stays balanced with other chemical reactions in the air and bodies of water through the carbon cycle.
Carbon is a component of all organic molecules, many of which are essential for life. The ultimate source of all organic molecules is primary production, in which photosynthetic organisms take in carbon dioxide gas (or bicarbonate - CO2's water-dissolved form) and, using sunlight as an energy source, convert it into glucose.