Tuesday, March 20
Bell Work:
If I give you the word PRODUCER, what other words and connections could you draw from this? Use a concept map if it helps.
All ecosystems depend on producers because they are the basis for the ecosystem's energy.
*Producers are also called autotrophs because they make their own food.
How does an animal that eats only meat rely on producers for energy?
Most producers use sunlight to make food.
Formula for photosynthesis:
6CO2 + 6H2O + energy C6H12O6 + 6O2
Chemosynthesis­ process by which an organism forms carbohydrates using chemicals as energy.
Chemosynthetic organisms are found in deep­sea vents, sulfur­rich salt marsh flats and hydrothermal pools. (What kingdom would these bacteria belong to?)
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Consumers- organisms that get their energy by eating other living
or once-living resources.
*Also called heterotrophs
-Herbivore -eats only plants
-Carnivore -eats only other animals
-Omnivore -eats both plants and animals
-Detrivore -eat dead organic matter
-Decomposer -detrivores that break down organic matter into
simpler compounds
-Specialist- consumers that primarily eat one specific organism or a
very small number of organisms
-Generalist- are consumers that have a varying diet
Food Chains
A food chain links species by their feeding relationships.
A food chain follows the connection between one producer and a single chain of consumers within an ecosystem.
­Arrows indicate direction energy is being transferred
­Simple model with 3­4 transfers usually
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Trophic Levels
*Producers are at the bottom level. *Herbivores are at the second trophic level. (Primary Consumers)
*Carnivores are at the highest trophic level. (Secondary Consumers)
*Tertiary Consumers eat secondary consumers.
Food Webs
A food web shows a complex network of feeding relationships.
An organism may have multiple feeding relationships within an ecosystem.
A food web emphasizes the complicated feeding relationships and energy flow in an ecosystem.
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Using the food web on page 410, how can the reef shark be both a secondary and tertiary consumer?
Energy Pyramid shows decrease in energy available as the trophic level goes higher.
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Biomass­ measure of the total dry mass of organisms in a given area. (Each level represents the amount the level above needs to consume to meet its needs)
­when a consumer eats a producer, a great deal of energy is transferred in the process as heat and waste.
Tertiary Consumers
Fisherman 75 g/m2
Secondary Consumers­
Large Fish 150g/m2
Primary Consumers­ Small fish 675 g/m2
Producers ­ 2000 g/m2
Sea plants, kelp, seaweed
Biomass Pyramid
Pyramid of Numbers
Tertiary Consumers
Mountain Lion
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Secondary Consumers
Snakes, Foxes, Hawks
5000
Primary Consumers­ rabbits, squirrels, birds 500,000
Producers (Grasses/Plants) 5,000,000
Shows the number of individuals at each trophic level in an ecosystem.
Helpful in showing the vast number of producers required to support even a few top level consumers.
In some cases a pyramid of biomass and a pyramid of numbers is inverted (misleading) because in the case of a large tree, the number of consumers would outnumber the producers.
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