Reporting Category 5 Interdependence Within Environmental Systems. Station 17. Interactions Through Trophic Levels. Essential Question – Bell Ringer. Why is it necessary for the number of prey to be greater than the number of predators in order for an ecosystem to be balanced?
Interdependence Within Environmental Systems
Interactions Through Trophic Levels
Why is it necessary for the number of prey to be greater than the number of predators in order for an ecosystem to be balanced?
The series of steps in which a large fish eats a small fish that has eaten algae is:
The diagram below shows a food web in a large park. Each circle represents a different species in the food web. Which of the organisms in the food web could be referred to as primary consumer(s)?
1 – Create a food chain out of each card set and write it in your journal
Explain the 10% rule of an ecosystem using the information from the ecological pyramid and the glossary.
The 10% rule is a general rule that helps explain that the amount of energy in an ecosystem is reduced by 90% when it flows from one trophic level to the next. For example, in the ecological pyramid, the grasses (producer level) provide only 10% of the energy they receive to the grasshopper (primary consumer level). The other approximately 90% of the energy in the grass is not lost—it’s used for other purposes. Each successive trophic level in an ecosystem receives only about 10% of the energy available from the previous level.
Which example, a food chain or a food web, provides a more realistic picture of the flow of matter and energy in an ecosystem? Support your answer.
A food web provides a more realistic representation of the interactions that occur in an ecosystem. For example, the food web in Question 6 shows that the mockingbird has three sources of food: the butterfly, the house fly, and the grasshopper. The food chain from Question 3, which shows only the butterfly as a source of food for the mockingbird, gives a much more simplified view of the flow of matter and energy in the ecosystem.
Energy pyramids show the most available energy at the base and the least amount of energy at the top. What accounts for the difference in the energy levels in these two parts of the energy pyramid?
Looking at the energy pyramid above, which best explains why a pyramid is used to represent the energy flow within an ecosystem?
In the biomass energy
Pyramid to the right, which
Level contains 10% of the
energy from the producer?