Communities & Ecosystems Food Web Poster - Assignment Example

Communities & Ecosystems – Food Web Based on the above food chain plant is autotroph because they make their own food through a process of photosynthesis. Plants get energy from the sun and convert it into food. While heterotrophs are organism which does not make their own food, but they depend on autotroph, from above food web, heterotrophs are grasshopper, caterpillar and aphids.

Consumers are organisms that survive by eating other dead or alive organism. Owl, bird, mice, spider and ladybird are consumers. Detritivores are organism that feed on decomposing matter, mainly dead plant or animal waste, earthworm is an example of detritivores. While saprotrophs helps in speeding up decomposition of matter, they act like detritivores but decomposition of matter by saprotrophs happens externally as opposed to detritivores that consume dead organism (Begon et al 326).The food chain The food chain is a description of the relationship between different feeding organisms.

Plant Top of FormBottom of Formgrasshopper, mice owl The above example is a food chain, it shows that one organism such as grasshopper depends on another organism such as a plant (Begon et al 595).Food web describes a collection of food chains. Food web shows different organism depending on more than one organism. This because some organisms such as owl as shown above on food web do not rely on one source of food like grasshoppers that only eats grass.

Tropical levels are different levels in the food chain where organisms are categorized into either producers or consumers. This level depicts the transfer of energy from one level to another level. There are different levels in a food chain. For example, in a food chain above, first level comprises of producers, second level are herbivorous that feeds on plants. The next level is carnivorous which depends on herbivorous. Highest level is carnivorous that eats other small carnivorous owl is an example (Rastogi and Kishore 72).

The first energy comes from the sun where it is used by plants to make food hence generating energy. The nutrient made from a plant through photosynthesis keeps plants alive. Energy is transferred to herbivorous as the first consumers of plants. The transfer of energy goes on up to the last of tertiary consumers. All energy from the sun is not used by the plant. When herbivorous consume plant to gain energy not all the plant nutrients are used to create energy, some are lost through passing out of feces.

Herbivorous uses the energy gained from food consumption, but some energy is lost through respiration and heat loss (Rastogi and Kishore 75).The shape of pyramid varies as it rises to the top based on the fact that energy is lost from one level to another as stated above. From the food web above, not all grass is eaten by grasshopper to gain all energy transferred from the sun through photosynthesis. Energy drops from one level to another as it is depicted by a pyramid (Rastogi and Kishore 73).

Energy enters and leaves ecosystem because it is lost through heat when organism use the gained energy from another level. For example, the energy transferred from plant to herbivorous is lost because it uses it during movement. Nutrients are recycled because they pass from one organism to another. For example, plant obtains nitrate from nitrogen in soil where it uses to make nutrients such as amino acids. Herbivorous uses nutrients from plants to get energy, amino acid from plant is eliminated from herbivorous through urea.

Bacteria from the soil turns urea back to nitrate, which is then used by plant hence is form of cycle. Saprotrophic bacteria and fungi decomposes dead bodies to obtain energy, however, not all energy is used by decomposers, some left for another organism such as plants. The available energy not utilized by decomposers is used by plants in the form of nutrients (Dighton 7).Work citedBegon Michael, Townsend R. Colin and Harper L. John. Ecology: From Individuals to Ecosystems. UK: John Wiley & Sons, 2009. Print.Dighton John.

Fungi in Ecosystem Processes. New York: CRC Press, 2003. Print.RastogiV. B. and Kishore B. A Complete Course in ISC Biology. New Delhi: Pitambar Publishing, 1997. Print.