1. YOU NEED YOUR TEXT BOOKS!
JQ: How much energy does it take to produce a filet mignon?

2. Ecosystem Energy
In ecosystems, energy moves through these niches:
autotrophs - produce
food by photosynthesis
heterotrophs - consume
autotrophs and other
heterotrophs
decomposers -
rearrange organic materials into nutrients for autotrophs
The amount of energy available to support life or the largest population that can be sustained by the available resources is called the carrying capacity.

3. Food chains represent the steps in transferring energy through the ecosystem. Complex and integrated food chains are called food webs.
Energy can be represented by trophic pyramids that compare the number of organisms in a population, or the weight (biomass) of organisms, or the productivity (energy calories).

4. Generally, only 10% of the energy is passed on to the next higher level.
Why does the amount of energy change if energy is never created or destroyed?
1. It can be converted into unusable forms such as heat or for an organisms’ respiration, metabolism, and predation.
2. Not all parts of an organism have food value or provide calories. ex: bones, scales
USDA

5. The amount of energy available is calculated as net productivity or primary productivity.
Primary productivity of the ocean is billion tons of carbohydrates (mostly glucose).
Gross productivity - respiration = net productivity given in units of g/m2/yr.
Respiration is the amount of energy used at each level to maintain life (estimated at 90% of the available calories).
If one trophic level has 100,000 calories available, only 10,000 can potentially be transferred to the next trophic level.

6. phytoplankton
krill
baleen whale
The more levels in the ecosystem pyramid the less energy is available in a useable form at the next higher level.
Shorter food chains are more efficient. The reason the ocean can support the tremendous expense of endothermic (warm-blooded) mammals is because they eat low on the food chain.