Information About ™Food Chain |
| CATEGORIES ABOUT FOOD CHAIN | |
| ecology | |
| SHOPPER'S DELIGHT | |
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As usually diagrammed, an Organism is connected to another organism for which it is a source of Food Energy and Material by an arrow representing the direction of Biomass transfer. Organisms are grouped into Trophic Level s—from the Greek for nourishment, trophikos—based on how many links they are removed from the Primary Producer s. Primary producers, or Autotroph s, are species capable of producing complex organic substances (essentially "food") from an energy source and inorganic materials. These organisms are typically Photosynthetic Plants or algae, but in rares cases, like those organisms forming the base of deep-sea vent food webs, can be Chemotroph ic. All organisms that eat the Autotrophs are called Heterotrophs . They get their energy by eating the producers. FOOD CHAIN A food chain describes a single pathway that energy and nutrients may follow in an ecosystem. There is one organism per trophic level, and trophic levels are therefore easily defined. They usually start with a primary producer and end with a top Predator . Here is an example of a food chain: :: Phytoplankton → Copepod → Fish → Squid → Seal → '' Orca '' This "chain" can be described as follows: Killer whales (''Orca'') feed upon seals, that feed upon squid, that eat small fish, that feed on copepods, that feed on microscopic ). Food chains are overly simplistic as representatives of what typically happens in nature. The food chain shows only one pathway of energy and material transfer. Most consumers feed on multiple species and are, in turn, fed upon by multiple other species. The loss of energy through the levels causes the species at the top to be less numerous. On average 10% of the organism's energy is passed on to its predator. FOOD WEB A food web or '''food network''' extends the ''food chain'' concept from a simple linear pathway to a complex network of interactions. The direct steps as shown in the food chain example above seldom reflect reality. This "web" makes it possible to show much bigger animals (like a whale) eating very small organisms (like plankton). Food sources of most species in an ecosystem are much more diverse, resulting in a complex ''web'' of relationships as shown in the figure on the right. In this figure, the grouping of Phytoplankton → Herbivorous Zooplankton → Carnivorous Zooplankton → Arctic Char → Capelin on the far right is a ''food chain''; the whole complex network is a ''food web/network''. EXTERNAL LINKS
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