4.1.6 trophic levels

• Trophic level is the position an organism occupies within its food chain
• predator - consumer that eats other animals
• prey - animals that the predators eat
• apex predators - sit at the top of food chain, not preyed upon
• decomposers - recycle organic matter within ecosystem. final stop for all food chains. break down dead material by secreting enzymes. enzymes partly digest waste products, producing small + soluble molecules. small molecules then diffuse into decomposer
• trophic pyramid - shows how energy flows through different trophic levels. biomass decreases with each successive trophic level due to energy loss during respiration
• energy flow diagram - shows where energy comes from and goes to in an ecosystem
• pyramids are usually wider at base than at top because there are more producers than consumers
• food chain - level 1 - producers. use light energy from sun to produce food (algae, plants...)
• level 2 - primary consumers. eat producers. herbivores
• level 3 - secondary consumers. eat primary consumers. carnivores
• level 4 - tertiary consumers. eat secondary consumers. omnivores
• level 5 - quaternary consumer. eats tertiary consumers. rare
• food web - interconnected network of food chains within an ecosystem