1. Food Web Questions Page 46 and 47

2. Draw five food chains based on the food web shown in fig. 2.10  Seeds- mouse- snake

3. Food Web versus Food Chain  Food chains are one model of food relationships. Each producer is eaten by more than one primary consumer and so on. Therefore the food relationships, in an ecosystem, looks more like a web than a chain

4. Energy Flow  In an ecosystem, energy always flows from what is being eaten to the organism that is eating. For example, if a robin eats a caterpillar, the energy flow is directed from the caterpillar to the robin.  This is indicated in a food chain by an arrow

5. Biomass  Biomass is the total mass of organisms in an ecosystem  Biomass is related to food chains because it takes a greater number of organisms at the lower levels to feed the organisms at the higher levels.  The result is that energy flow in an ecosystem looks like a pyramid

7. Assignment  Draw your own food chain using things that you eat.  Label it with: producer, primary consumer, secondary consumer, tertiary consumer  Use arrows to indicate the flow of energy  Question: Some people have a limited food source. What might happen if their food supplies were damaged by a hurricane, or war.