This study reports a collective case study of five science education graduate students to highlight the role of culture as an influential component within their conceptual understandings of urban science education. Conceptual change theory was used as a theoretical framework to explore the negotiations that five graduate students experienced during a semester-long 'Urban and Multicultural Science Education' course geared toward increasing conceptual complexity (i.e., the ways students make connections between concepts). Negotiation--the way these students' adopted, resisted, or considered new inter-conceptual complexity--was studied through how these learners activated and applied their understandings. Findings support that culture influenced the development of conceptual complexity for the themes studied by increasing the permeability of concepts to connect to one another--coined here as "conceptual porosity." This complexity is represented through the inter-conceptual connectivity that developed temporally during learning experiences. Implications for these findings are discussed, as well.