Original Project
Interdependence in Ecosystems
Item ID027005: Changes in a population in a food web (grasshoppers) can affect the populations of both its predator (frogs) and its prey (grass).
The diagram below shows the feeding relationships between populations of organisms in an area. The arrows point from the organisms being eaten to the organisms eating them.
Using only the relationships between the organisms shown in the diagram, if most of the grasshoppers are killed, which of the following describes what will happen to the amount of grass and the number of frogs?
- The amount of grass will increase, and the number of frogs will decrease.
- The amount of grass will decrease, and the number of frogs will increase.
- The amount of grass will increase, and the number of frogs will stay the same.
- The amount of grass will stay the same, and the number of frogs will decrease.
- Distribution of Responses
- Students Responding Correctly
| Group | Correct | Total | Percent |
|---|---|---|---|
| Overall | 2461 | 3287 | 75% |
| Grades | |||
| 6–8 | 518 | 790 | 66% |
| 9–12 | 1935 | 2484 | 78% |
| Gender | |||
| Male | 1160 | 1540 | 75% |
| Female | 1245 | 1671 | 75% |
| Primary Language | |||
| English | 2220 | 2925 | 76% |
| Other | 166 | 256 | 65% |