Unit 4 Ecosystems

About This Unit:

You will learn about the resources within ecosystems which organisms compete for such as organic material, sunlight, and mineral nutrients. You will learn to identify the various critical factors influencing community dynamics such as the components of its physical and geographic environment. The unit then introduces you to how organisms acquire energy and how that energy is passed from one organism to another through food webs and their constituent food chains. You will gain an understanding of the different trophic levels, such as producers, consumers and decomposers, and how energy transfers affect ecosystem structures and dynamics. You will also learn about how the structure of ecosystems can be visualized and modeled with ecological pyramids to show the relative amounts of various parameters (such as number of organisms, energy, and biomass) across trophic levels. Finally, you will be introduced to the biogeochemical cycle, which is the process of recycling inorganic matter between living organisms and their environment. The six most common elements associated with organic molecules are covered explaining how mineral nutrients are cycled from one living organism to another, and between the biotic and abiotic world. You will also gain an understanding of how human activities have impacted these biogeochemical cycles and the potential consequences for society.