Learning Objectives

For the problem tasks presented here, the objective is to help students develop an interconnected way of thinking about biological processes; to reason by consider multiple levels of biological organization. The intent is to provide opportunities in an ecology context for students to account for biological phenomena by considering the underlying molecular interactions (Hmelo-Silver & Pfeffer, 2004; Lin & Hu, 2003; Marbach-Ad, Rotbain & Stavy, 2008; Penner, 2000; Wilensky & Reisman, 2006). For ecological phenomena, ecologists draw on an understanding of biologically mediated processes including energy flow, matter cycling, respiration, photosynthesis, decomposition, and interrelationships among these processes to explain natural phenomena such as the functioning of a simple ecosystem. Students, on the other hand, when trying to make connections between objects to explain a phenomenon, often claim, “all things are connected”, or refer to “the circle of life” (Grotzer & Basca, 2003; Maskiewicz, 2006). This claim, however, usually represents only organismal level connections (Anderson, Mohan, & Sharma, 2005; Grotzer & Perkins, 2000; Hogan, 2000). Although students recognize that objects in a system interact and affect each other, they do not extend this view beyond local phenomena, nor do they consider the underlying processes that result in the observed phenomena (Ben-Zvi Asaraf & Orion, 2005; Hmelo-Silver & Pfeffer, 2004; Hmelo-Silver, Marathe & Liu, 2007). One way of understanding that would contribute to the development of an interconnected way of thinking is to understand living organisms as matter and energy transforming systems, including bacteria.

Two tables are included below. The first provides an overview of the design and development of the problem situations. The second table was developed by Josh White (2013) and links the problem situations to the Next Generation Science Standards and the California Science Standards.