In this video Paul Andersen explains how matter moves from the environment into living organisms and back into the environment. Food webs are used to show how matter and energy move through organisms. Ecological pyramids show that matter and energy are lost as they move from producers to consumers.
In this video Paul Andersen explains the important relationships that exist in ecosystems. He starts by delineating between organisms and their environment. He explains how food webs can be used to show energy and matter flow in a community. He describes the levels studied within ecology and explains how population interact at the level of a community. He finishes be describing population growth and carrying capacity.
In this video Paul Andersen explains how systems can be used to understand phenomenon in science and create better designs in engineering. He starts by defining the characteristics of a system and describes how system models can be used to better understand the world. For example a system model of the water cycle can show the cycling of matter on the surface of the Earth. He ends with a progression of instruction for a K-12 science classroom.
Paul Andersen explains the importance of modeling in science and engineering. Models are used by scientists to explain phenomenon. Unlike mental models, conceptual models can be shared by all scientists to improve our understanding of the Universe. Engineers use models study systems and test designs.