Need a summary based on my abstract, written exam, and annotated bibliography. these thinkers. Please review those first.
The first thing to consider as you revise your written exam is to clarify some key terms, which need to be defined in relation to some key thinkers (not based on encyclopedia entries, never a good idea for this kind of papers).
So, when you examine, for instance, the notions of modernism, postmodernism and the contemporary you need to clearly refer to philosophers who have discussed these topics and have provided definitions for them. These are the first key terms you need to unpack.
The thesis statement needs to be clearer and more compelling, making a case to why we should care about the curve in art. Why does it matter, what is it contributing to the philosophical/aesthetic discourse? Most importantly, how can you develop a non-formalist analysis of curvilinearity that can indeed include the conceptual and what you call the shift from aesthetic to meaning? That shift will take you from the analysis of modernist aesthetic largely predicated on a Kantian formalism to a postmodern aesthetic based on historical and social hermeneutics (from Hegel to Marx and beyond).