Producers/Autotrophs Manufacture their own food; they don’t eat. Most producers use photosynthesis (energy from the sun) Autotrophic bacteria use chemosynthesis (energy from chemicals in the environment)

Biomass The mass of organic (living) material in the environment. Net Primary Productivity -how much photosynthesis or chemosynthesis is occurring The rate at which energy is turned into food. So which ecosystems have the greatest net primary productivity?

Bonus Point Question: What’s an estuary???

Consumers/Heterotrophs Obtain energy by eating. Herbivores Eat producers. Carnivores Eat other consumers. Omnivores Eat both producers and consumers.

Detrivores Feed on the waste of an ecosystem. Trivia question : Why do scientists believe that vultures have bald heads?

Decomposers A class of detrivores that includes bacteria and fungi. Break down dead tissue and waste into simpler molecules. Return some of those molecules to the soil to be reused by autotrophs.

When one organism eats another, energy is transferred (Energy flows from producers to consumers.) Trophic level shows the organism’s position on the energy transfer chain

Food Chain : A path of feeding relationships Food Web : All of the different food chains in an ecosystem. Who are the detrivores in this food web?

Quick Fact… Roughly 10% of the energy of one trophic level can be transferred to the next level of consumers. But why is that? Amount of Energy

Some organisms are never eaten Organisms use up most of the energy they make/eat for cell respiration, movement, maintaining body temp, reproduction, etc. Only a small amount is stored. The digestive process is inefficient; E is wasted Amount of Energy So how does this affect the numbers of organisms at each level?

“If you go on safari in Kenya or Tanzania, for example, you will see about 1,000 zebras, gazelles, wildebeest, and other herbivores for every lion or leopard you see, and there are far more grasses, trees, and shrubs than there are herbivores.” (p. 419)

Think about it… In theory, if we wanted to use our food supplies in the most efficient way, should humans be carnivores, herbivores or omnivores? Herbivores