Mpodozis J., Letelier J. C., Concha M. L. & Maturana H. R. (1995) Conduction velocity groups in the retino-tectal and retino-thalamic visual pathways of the pigeon (Columbia livia). The International Journal of Neuroscience 81(1–2): 123–136.

Mpodozis J., Letelier J. C., Concha M. L. & Maturana H. R.
(

1995)

Conduction velocity groups in the retino-tectal and retino-thalamic visual pathways of the pigeon (Columbia livia).
The International Journal of Neuroscience 81(1–2): 123–136.
Varela F. J., Letelier J. C., Marín G. & Maturana H. R. (1983) The neurophysiology of avian color vision. Archivos de Biología y Medicina Experimentales 16: 291–303.

Varela F. J., Letelier J. C., Marín G. & Maturana H. R.
(

1983)

The neurophysiology of avian color vision.
Archivos de Biología y Medicina Experimentales 16: 291–303.
Zaretzky A. N. & Letelier J. C. (2002) Metabolic networks from (M, R)-systems and autopoiesis perspective. Journal of Biological Systems 10(3): 265–280.

Zaretzky A. N. & Letelier J. C.
(

2002)

Metabolic networks from (M, R)-systems and autopoiesis perspective.
Journal of Biological Systems 10(3): 265–280.
This paper is the first one of a series devoted to the analysis of metabolic networks. Its aim is to establish the theoretical framework for this analysis. Two different lines of research are considered: the one about metabolism-repair systems ((M, R), introduced by Robert Rosen as an abstract representation of cell metabolic activity, and the concept of autopoiesis developed by Humberto Maturana and Francisco Varela. Both concepts have been recently connected by Letelier et al., determining that the set of autopoietic systems is a subset of the set of general abstract (M, R) systems. In fact, every specific (M, R) system is an autopoietic one, being the boundary, which specifies each system as a unity, the main element of autopoietic systems which is not formalized in Rosen’s representation. This paper introduces the definition of boundary – a physical boundary and a functional one – for (M, R) systems in the context of a representation using category theory. The concept of complete (M, R) system is also introduced by means of a process of completion in categories which is functorial, natural and universal.