Energy Flow Energy Pyramids Ch 3 2 Note

Energy Flow & Energy Pyramids (Ch 3 -2) Note #6

How does Energy flow through an Ecosystem? ANS: Moves in one direction from the sun to autotrophs to heterotrophs

Closer look at Feeding Relationships 1. Food Chain: a link between those who eat and those that get eaten. Ex. Direction of feeding ------>

2. Food Webs: Interconnected food chains in an ecosystem. Ex. [Secondary Consumers] [Producers] [Primary Consumers] [Top-level Consumers]

Ecological Pyramids Trophic Levels: Traces Energy levels in food chain (4 -5 level in a pyramid) (3 types) 1. Energy Pyramid: Traces the loss of energy (10%) at each trophic level

Trophic Level 4 Levels 10% of 10 passed on 10% of 1000 passed on 90% of 1000 used by organism 100 % of Sun’s Energy is absorbed-------> ONLY 10% of energy from previous level is passed on

2. Biomass Pyramid: traces how much total mass a living thing contributes to its environment. Trophic Levels 4. Top Consumers 3. Secondary Consumers 2. Primary Consumers 1. Producers 5 kg of hawks 50 kg of snakes 500 kg of mice 5000 kg of rice Producers Which trophic level contributes the most mass? _______

3. Pyramid of Numbers: traces how many organisms are @ each trophic level. Trophic Levels 4. Top Consumers 3. Secondary Consumers 2. Primary Consumers 1. Producers 50 hawks 500 snakes 10, 000 field mice 1 million flowers & grass

Constructing A Food Web

Food Chain 1