In systems biology, networks represent components of biological systems and their interactions. It is a challenge to efficiently represent, integrate and analyse the wealth of information that is now being created in biology, where issues concerning consistency arise. As well, the information offers novel methods to explain and explore biological phenomena. To represent and reason with inconsistency as well as provide explanation, we represent a fragment of a biological system and its interactions in terms of a computational model of argument and argumentation schemes. Process pathways are represented in terms of an argumentation scheme, then abstracted into a computational model for evaluation, yielding sets of 'consistent' arguments that represent compatible biological processes. From the arguments, we can extract the corresponding processes. We show how the analysis supports explanation and systematic exploration in a biology network.