During this Unit, students will specifically focus on the concept of ecosystems and the adaptations made by organisms to survive in them.
Through experiments aimed at modeling food chains and food webs, students will begin to understand how a disturbance in one segment of an ecosystem can affect other, if not all, segments of that system.
Students will come to appreciate that plants and animals in ecosystems are directly and indirectly affected by non-living components of the system, such as soil, precipitation, and temperature. By performing experiments, they will see that certain adaptations are required for plants and animals to survive in one ecosystem versus another.
The concept of adaptation is further developed in experiments in which students will find that specific body structures can provide one species with a survival advantage over other species. In these same experiments, students will see that over long periods of time the environment in which organisms live may change and that organisms that cannot adapt to the changes may loose in competition to other species and become extinct. Further, the concept of extinction events in the fossil record is introduced in analyzing their experimental results.
Students will perform experiments that model the impact of the introduction of pollutants into environment. Through analysis, students will ascertain the effect of lethal levels of toxins on animals that consume contaminated plants. They will also see how the impact of pollution moves up the food chain, from contaminated plant producer, to herbivore consumers, and finally to carnivorous predators.
The ultimate goal of this Unit is to have students begin to understand and appreciate how fragile and interconnected ecosystems are. Ultimately, through experiments involving pollution, students will see that human beings are important members of ecosystems and that they can damage ecosystems and their own environment. They will appreciate that they themselves are interconnected to other organisms and non-living components of the ecosystems in which they live.
Conceptual Themes addressed in this Unit:
- Structure and Function
- Changes and Reactions