This paper explores the similarities between the conceptual structure of quantum theory and relational biology as developed within the Rashevsky-Rosen-Louie school of theoretical biology. With this aim, generalized quantum theory and the abstract formalism of (M,R)-systems are briefly presented. In particular, the notion of organizational invariance and relational identity are formalized mathematically and a particular example is given. Several quantum-like attributes of Rosen's complex systems such as complementarity and nonseparability are discussed. Taken together, this work emphasizes the possible role of self-referentiality and impredicativity in quantum theory.