category of (M,R)–systems

0.1 Metabolic-Replication Systems Rosen introduced metabolic–repair models, or (M,R)-systems in mathematical biology relational biologyPlanetmathPlanetmath) in 1957 ([4, 5]); such systems will be here abbreviated as MR-systems, (or simply MR’s). Rosen, then represented the MR’s in terms of categories of sets, deliberately selected without any structureMathworldPlanetmath other than the discrete topology of sets.

Theoreticians of life’s origins postulateMathworldPlanetmath that Life on Earth has begun with the simplest possible organism, called the primordial. Mathematicians interested in biology and this important question of the minimalPlanetmathPlanetmath living organism have attempted to define the functional relations that would have made life possible in a such a minimal system– a grandad and granma of all living organisms on Earth.

Definition 0.1.

The simplest MR-system is a relational model of the primordial organism which is defined by the following categorical sequence (or diagram) of sets and set-theoretical mappings: f:AB,ϕ:BHomMR(A,B), where A is the set of inputs to the MR-system, B is the set of its outputs, and ϕ is the ‘repair map’, or R-component, of the MR-system which associates to a certain productMathworldPlanetmathPlanetmathPlanetmath, or output b, the ‘metabolic’ component (such as an enzyme, E, for example) represented by the set-theoretical mapping f. Then, HomMR(A,B) is defined as the set of all such metabolic (set-theoretical) mappings (occasionally written incorrectly by some authors as {f}).

Definition 0.2.

A general (M,R)-system was defined by Rosen (1958a,b) as the network or graph of the metabolic and repair components that were specified above in Definition 0.1; such components are networked in a complex, abstract ‘organism’ defined by all the abstract relationsMathworldPlanetmathPlanetmathPlanetmath and connecting maps between the sets specifying all the metabolic and repair components of such a general, abstract model of the biological organism. The mappings bettwen (M,R)-systems are defined as the the metabolic and repair set-theoretical mappings, such as f and ϕ (specified in Definition 0.1); moreover, there is also a finite number of sets (just like those that are defined as in Definition 0.1): Ai,Bi, whereas fHomMRi(Ai,Bi) and ϕHomMRi[B,HomMRi(Ai,Bi)], with iI, and I being a finite index setMathworldPlanetmathPlanetmath, or directed set, with (f,ϕ) being a finite number of distinct metabolic and repair components pairs. Alternatively, one may think of a a general MR-system as being ‘made of’ a finite number N of interconnected MRi, metabolic-repair modules with input sets Ai and output sets Bi. To sum up: a general MR-system can be defined as a family of interconnected quartets: {(Ai,Bi,fi,ϕi)}iI, where I is an index set of integers i=1,2,,n.

0.2 Category of (M,R)–systems

Definition 0.3.

A categoryMathworldPlanetmath of (M,R)-system quartet modules, {(Ai,Bi,fi,ϕi)}iI, with I being an index set of integers i=1,2,,n, is a small category of sets with set-theoretical mappings defined by the MR-morphisms between the quarted modules {(Ai,Bi,fi,ϕi)}iI, and also with repair components defined as ϕiHomMRi[B,HomMRi(Ai,Bi)], with the (M,R)-morphismMathworldPlanetmath composition defined by the usual composition of functions between sets.

With a few, additional notational changes it can be shown that the category of (M,R)-systems is a subcategoryMathworldPlanetmath of the category of automataPlanetmathPlanetmath (or sequential machines), 𝒮[M,A] ([7, 8]).

0.2.1 Remarks:

For over two decades, Robert Rosen developed with several coworkers the MR-systems theory and its applications to life sciences, medicine and general systems theory. He also considered biocomplexity to be an ‘emergent’, defining feature of organisms which is not reducible in terms of the molecular structures (or molecular components) of the organism and their physicochemical interactions. However, in his last written book in 1997 on “Essays on Life Itself”, published posthumously in 2000, Robert Rosen finally accepted the need for representing organisms in terms of categories with structure that entail biological functions, both metabolic and repair ones. Note also that, unlike Rashevsky in his theory of organismic setsPlanetmathPlanetmath, Rosen did not attempt to extend the MRs to modeling societies, even though with appropriate modifications of generalized (M,R)-system categories with structure ([7, 8, 13]), this is feasible and yields meaningful mathematical and sociological results. Thus, subsequent publications have generalized MR-system (GMRs) and have studied the fundamental, mathematical properties of algebraic categoriesPlanetmathPlanetmathPlanetmathPlanetmath of GMRs that were constructed functorially based on the Yoneda-Grothendieck Lemma and construction. Then it was shown that such algebraic categories of GMRs are Cartesian closed [7]. Several molecular biology realizations of GMRs in terms of DNA, RNAs, enzymes, RNADNA-reverse trancriptases, and other biomolecular components were subsequently introduced and discussed in ref. [21, 13, 14] in terms of non-linear genetic network models in many-valued, LMn logic algebras (or algebraic category of LMn logic algebras (

If simple (M,R)-systems are considered as sequential machines or automata the category of (M,R)-systems and (M,R)-system homomorphismsMathworldPlanetmathPlanetmathPlanetmathPlanetmathPlanetmathPlanetmathPlanetmath is a subcategory of the automata category. However, when (M,R)-systems are considered together with their dynamic representations the category of dynamic (M,R)-systems is no longer a subcategory of the category of automata.


  • 1 Rashevsky, N.: 1965, The Representation of Organisms in Terms of PredicatesMathworldPlanetmath, Bulletin of Mathematical Biophysics 27: 477-491.
  • 2 Rashevsky, N.: 1969, Outline of a Unified Approach to Physics, Biology and Sociology., Bulletin of Mathematical Biophysics 31: 159–198.
  • 3 Rosen, R.: 1985, Anticipatory Systems, Pergamon Press: New York.
  • 4 Rosen, R.: 1958a, A Relational Theory of Biological Systems Bulletin of Mathematical Biophysics 20: 245-260.
  • 5 Rosen, R.: 1958b, The Representation of Biological Systems from the Standpoint of the Theory of Categories., Bulletin of Mathematical Biophysics 20: 317-341.
  • 6 Rosen, R.: 1987, On Complex Systems, European Journal of Operational Research 30:129–134.
  • 7 Baianu, I.C.: 1973, Some Algebraic Properties of (M,R) – Systems. Bulletin of Mathematical Biophysics 35, 213-217.
  • 8 Baianu, I.C. and M. Marinescu: 1974, On A Functorial Construction of (M,R)– Systems. Revue Roumaine de Mathematiques Pures et Appliquées 19: 388-391.
  • 9 Baianu, I.C.: 1980, Natural Transformations of Organismic Structures., Bulletin of Mathematical Biology,42: 431-446.
  • 10 I.C. Baianu: 1977, A Logical Model of Genetic Activities in Łukasiewicz AlgebrasMathworldPlanetmathPlanetmath: The Non-linear Theory. Bulletin of Mathematical Biophysics, 39: 249-258.
  • 11 I.C. Baianu: 1983, Natural Transformation Models in Molecular Biology., in Proceedings of the SIAM Natl. Meet., Denver, CO.; Eprint is here available .
  • 12 I.C. Baianu: 1984, A Molecular-Set-Variable Model of Structural and Regulatory Activities in Metabolic and Genetic Networks., FASEB Proceedings 43, 917.
  • 13 I.C. Baianu: 1987a, Computer Models and Automata Theory in Biology and Medicine., in M. Witten (ed.), Mathematical Models in Medicine, vol. 7., Pergamon Press, New York, 1513–1577; Preprint No. EXT-2004-072:.
  • 14 I.C. Baianu: 1987b, Molecular Models of Genetic and Organismic Structures, in Proceed. Relational Biology Symp. Argentina; Preprint No.EXT-2004-067:MolecularModelsICB3.doc.
  • 15 I.C. Baianu, Glazebrook, J. F. and G. Georgescu: 2004, Categories of Quantum Automata and N-Valued Łukasiewicz Algebras in Relation to Dynamic Bionetworks, (M,R)–Systems and Their Higher Dimensional AlgebraPlanetmathPlanetmath, of Report is here available as a PDF and document
  • 16 R. Brown, J. F. Glazebrook and I. C. Baianu: A categorical and higher dimensional algebra framework for complex systems and spacetime structures, Axiomathes 17:409–493. (2007).
  • 17 L. Lo¨fgren: 1968. On Axiomatic Explanation of CompletePlanetmathPlanetmathPlanetmathPlanetmath Self–Reproduction. Bull. Math. Biophysics, 30: 317–348.
  • 18 Baianu, I.C.: 2004a. Łukasiewicz-Topos Models of Neural Networks, Cell Genome and Interactome Nonlinear Dynamic Models (2004). Eprint. Cogprints–Sussex Univ.
  • 19 Baianu, I.C.: 2004b Łukasiewicz-Topos Models of Neural Networks, Cell Genome and Interactome Nonlinear Dynamics). CERN Preprint EXT-2004-059. Health Physics and Radiation Effects (June 29, 2004).
  • 20 Baianu, I. C.: 2006, Robert Rosen’s Work and Complex Systems Biology, Axiomathes 16(1–2):25–34.
  • 21 Baianu I. C., Brown R., Georgescu G. and J. F. Glazebrook: 2006, Complex Nonlinear Biodynamics in Categories, Higher Dimensional Algebra and Łukasiewicz–Moisil Topos: TransformationsPlanetmathPlanetmath of Neuronal, Genetic and Neoplastic Networks., Axiomathes, 16 Nos. 1–2: 65–122.
Title category of (M,R)–systems
Canonical name CategoryOfMRsystems
Date of creation 2013-03-22 18:18:21
Last modified on 2013-03-22 18:18:21
Owner bci1 (20947)
Last modified by bci1 (20947)
Numerical id 64
Author bci1 (20947)
Entry type Topic
Classification msc 92B99
Classification msc 18-00
Classification msc 93A10
Classification msc 93A30
Classification msc 92B20
Classification msc 92B05
Synonym MR-systems
Synonym metabolic-replication systems
Related topic MathematicalBiology
Related topic SystemDefinitions
Related topic ArtificialInteglligence
Related topic ComplexSystemsBiology
Related topic IndexOfCategories
Defines MR-system
Defines general MR-system
Defines MR-quartet
Defines morphism of MR-quartets