- Slides: 17
Trophic Levels, Energy transfer and Pyramids
Producers • Sunlight is the main energy source for life on earth • Also called autotrophs • Use light or chemical energy to make food 1. Plants 2. plant-like protists (algae) 3. Bacteria
Consumers • Organisms that rely on other organisms for their energy and food supply • Also called heterotrophs
Trophic Levels – is the position an organism occupies in a food chain. It refers to food or feeding.
Trophic Levels (feeding levels) 3 2 1
Food Web Food webs are multiple food chains.
Food Webs Food webs show ALTERNATIVE PATHWAYS other possible pathways through which an organism can obtain energy
Energy Level Grass Mouse Grasshopper Frog Owl Hawk Producer, primary consumer, secondary consumer, tertiary consumer? 1 st producer 2 nd Primary consumer
Energy Level Producer, primary consumer, secondary consumer, tertiary consumer Producer Grass 1 st Mouse 2 nd Primary consumer Grasshopper 2 nd Primary consumer Frog 3 rd Secondary consumer Owl 3 rd and 4 th Hawk 3 rd Secondary and tertiary consumer Secondary consumer
Transfer of Energy lost from chain “link” to “link” is significant! Each level above only gets 10% of the energy from below
Energy lost from one trophic level (energy level) to the next level can be represented by a pyramid 4⁰ CONSUMERS 3 CONSUMERS 2 CONSUMERS 1 CONSUMERS PRODUCERS
ENERGY PYRAMID 1 J 100 J 1, 000 J 10, 000 J
Ecological Pyramid • • Which level has has the the most energy? most organisms? least energy?