Tuesday, 12 April 2011

Food Web

A food web is a graphical description of feeding relationships among species in an ecological community, that is, of who eats whom (Fig. 1). It is also a means of showing how energy and materials (e.g., carbon) flow through a community of species as a result of these feeding relationships. Typically, species are connected by lines or arrows called "links", and the species are sometimes referred to as "nodes" in food web diagrams.




Figure 1. A coastal food web in Alaska based on primary production by phytoplankton, and ending in predators of both land and sea. (Image courtesy U.S. Geological Survey)

You may try to build up a food web by enter this link :Dog Holding Halloween Pail Animated Clipart
http://www.gould.edu.au/foodwebs/kids_web.htm

Food Chain

1.  The food chain is the transfer of energy from one species to another.

2.  All living things needs energy for living beings to grow.

3.  Within a food chain, some living things create the energy (producers) and some use the energy (consumers).

4.Plants are producers of energy, as they make their own food (using sunlight, soil, and other elements).

5.  Animals are consumers, because they have to eat other animals and plants

6.  There are four different types of consumers in the animal kingdom. A carnivore is an animal that only eats other animals. An herbivore is an animal that only eats plants. An omnivore is an animal that eats both plants and animals. A scavenger is an animal that eats dead animals.

7.  The food chain can begin with a plant. The plant is then eaten by an insect. The insect is eaten by a bird. The bird is eaten by a large mammal. The mammal dies after being hit by a car. It decomposes and is broken down and used as food by bacteria and fungi.

8.  There are more than 100,000 different types of decomposer organisms. These simpler nutrients are returned to the soil and can be used again by the plants. Then the energy chain begins all over again.

9.  If one level is removed from the food chain, it can have disastrous results.

10.  Humans are at the end of the food chain. They eat both plants and animals that have consumed other forms of energy.

flower----> caterpillar----> frog----> snake
grass-----> deer------> wolf 

You may try to create your own food web by clicking the link : Poodle Strolling Animated Clipart http://www.vtaide.com/png/foodwebS.htm