Science ObjectDigital resources are stored online in your NSTA Library.
Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the first of three Science Objects in the Flow of Matter and Energy in Ecosystems SciPack. It explores the structure of the biomass in an ecosystem and overall cycling of matter. However complex the workings of living organisms, they share with all other systems the same physical principles that describe the conservation and transformation of matter.
Ecosystems are a community of interdependent organisms and the chemical and physical factors making up the environment with which they interact. For every ecosystem on Earth there is a particular biomass (matter) distribution among organisms in its populations. While the specific biomass distribution in any given ecosystem is unique because of resource availability, there is a common overall biomass distribution pattern in all ecosystems. Greater biomass exists in populations that obtain matter from the physical environment than in populations that obtain matter from other living organisms. As matter flows through different levels of organization in living systems—cells, organs, organisms, communities—and between living systems and the physical environment, chemical elements are recombined in different ways. Matter is conserved through each change.
- Define an ecosystem and understand how it comprises an interdependent community of organisms along with their interactions with the chemical and physical components of the environment
- Categorize organisms in a community based on their sources of matter/biomass and nutrients as one of the following: producers, herbivores (primary consumers), carnivores (secondary consumers; tertiary or top-consumers),
- omnivores, and decomposers
- Predict the relative biomass for different levels in a biomass pyramid for a typical ecosystem
- Explain how matter is conserved in the interactions between consumers and producers, but that in a biomass pyramid there is less biomass at the consumer level compared to the producer level