Module Description & Pacing Guide

The idea of a system is one of the grand integrating (crosscutting) concepts that pervades all of science. In the Living Systems Module, students start by looking at Earth as the interaction of four Earth systems or subsystems—the geosphere, the atmosphere, the hydrosphere, and the biosphere. The focus of the module then turns to the biosphere as students explore the phenomenon of ecosystems and organisms in terms of their interacting parts. The driving question for the module is how can we describe Earth’s biosphere as a system of interacting parts?

In this module, students think about systems on different scales— nutrient and transport systems within an organism that moves matter and provides energy to the individual organism, and feeding relationships in ecosystems that move matter among plants, animals, decomposers, and the environment. Students come to understand through a variety of experiences that plants get the materials they need for growth primarily from water and air, and that energy in animals’ food was once energy from the Sun. There are many opportunities for students to explore how human activities in agriculture, industry, and everyday life can have major effects on these systems. Students gain experiences that will contribute to the understanding of crosscutting concepts of patterns; scale, proportion, and quantity; systems and system models; and energy and matter.