The Food Chain
Click here to be joined by your audio host!
What is the difference between the 'Food Chain'
and 'Food Web?'
A popular misnomer, the 'food chain' is not actually a linear chain
but a complex web. Energy is passed from one organism to another
in a complex network like a spider's web.
The food chain consists of four main parts:
This table shows the relational biomass
of each of the major groups in the food chain:
\ | | | | | | | |
| | | | | | /
The Sun, which provides the energy for everything on the planet.
Producers: these include all green plants. These are also
known as autotrophs, since they make their own food. Producers are
able to harness the energy of the sun to make food. Ultimately, every
(aerobic) organism is dependent on plants for oxygen (which is the waste
product from photosynthesis) and food (which is produced in the form of
glucose through photosynthesis). They make up the bulk of the food
chain or web.
Consumers: In short, consumers are every organism that eats something
else. They include herbivores (animals that eat plants), carnivores
(animals that eat other animals), parasites (animals that live
off of other organisms by harming it), and scavengers (animals that
eat dead animal carcasses). Primary consumers are the herbivores,
and are the second largest biomass in an ecosystem. The animals that
eat the herbivores (carnivores) make up the third largest biomass, and
are also known as secondary consumers. This continues with tertiary
Decomposers: These are mainly bacteria and fungi that convert dead
matter into gases such as carbon and nitrogen to be released back into
the air, soil, or water. Fungi, and other organisms that break down
dead organic matter are known as saprophytes. Even though
most of us hate those mushrooms or molds, they actually play a very important
role. Without decomposers, the earth would be covered in trash.
Decomposers are necessary since they recycle the nutrients to be used again
How have humans affected the food chain?
When we spray pesticides, we put the food chain
in danger. By breaking one link on the chain means all of the organisms
above that link are in threat of extinction (like the domino effect).
By hunting animals nearly to extinction, everything above the animal in
the food chain is put in danger. A 'chain reaction' in the food chain
can be perilous! Since the food chain provides energy that all living
things must have in order to survive, it is imperitive that we protect
[ Topics | Welcome | Eco-consciousness | Search | Chat | Quiz | Bulletin Board | Ecosystems | Ecology | Children | Endangered Animals | Art Restoration | Ways to Help | Success Stories | Pollution Alerts | War | Did you know? | Comments | Links & Credits ]