NOTE: (For Food Chain/Web, see: IRC: Food Chains and Food Webs)

Current TEKS:

7.12 A:  identify components of an ecosystem

7.12 B:  observe and describe how organisms including producers, consumers, and decomposers live together in an environment

7.12 C:  describe how different environments support different varieties of organisms

Future TEKS:

7.10 B:  describe how biodiversity contributes to the sustainability of an ecosystem

8.11 A:  describe producer/consumer, predator/prey, and parasite/host relationships as they occur in food webs

Scope & Sequence:

Aldine: Grade 7, 5th six weeks                Cy-Fair: Grade 7, 5th six weeks; Grade 8, 5th six weeks

Big Ideas:

Producers are living organisms that produce complex organic compounds from simple inorganic molecules using energy from light (by photosynthesis) or inorganic chemical reactions. Most modern producers utilize sunlight to fuel photosynthesis. Plants are terrestrial producers, while algae are marine producers; both utilize photosynthesis. Bacteria around deep sea vents do not have access to sunlight as a source of energy, so they oxidize other inorganic compounds.

Consumers are living organisms that consume organic compounds to convert to energy. There are several types of consumers: herbivores, omnivores, carnivores. Herbivores are consumers that ingest only producers like plants, and are known as primary consumers. Types of herbivores include deer, cattle, and giraffes. Omnivores are consumers that ingest both plants and other consumers as well as possibly some decomposers. Carnivores consumers that ingest only other consumers. Carnivores often have special adaptations that allow them to better compete for resources, meaning they

Decomposers are living organisms that ingest dead and/or decaying material to obtain energy. The most common decomposers are fungi and bacteria.

The Grabber:

The Enchanted Sea - 3:05 min. video from YouTube showing manta Rays feeding on plankton

Case Study:

Phytoplankton and the World's Oceans

Phytoplankton are plankton species that utilize photosynthesis as a means to convert inorganic compounds into simple organic compounds, which they use for food. Phytoplankton live in the upper 200 m of ocean waters, and live in oceans across the globe both East to West and North to South. Phytoplankton are responsible for roughly half of the world's photosynthesis processes. They provide the base of a food web for a large percentage of all life on planet Earth. This accounts for the largest single biological sink for CO2, a major player in global. Scientists are trying to use plankton to fight global. The concept is simple, more plankton means more CO2 being sucked out of the atmosphere.

For more information on phytoplankton, see What are Phytoplankton? from NASA. For more information on using phytoplankton as a tool to fight global warming see Recruiting Plankton to Fight Global Warming from the NY Times.

Good Questions for Research:  

          What role does phytoplankton have in the ocean's ecosystem?

                    This introduces th concept of identifying an organism as a producer, consumer, or decomposer by its characteristics.

          How does phytoplankton affect oceanic consumers?

                    This relates producers roles to those of consumers, but in a different example than terrestrial plants.

          How does phytoplankton affect oceanic decomposers?     

                    This questions makes the student think in terms of how a food chain interacts.

          How do phytoplankton respond to environmental change?

                    This allows students to relate global change first to an individual species, and then to how that could impact the ecosystem.

Not So Good Questions for Research:

Do phytoplankton respond to change?

          This question is oversimplified and does not open the door to discuss on change to a species and its respective ecosystem & food web.

Simulated Research Activities: