might motivate the examination of membrane systems from the point of view of the concurrent nature of their Membrane systems [5] are biologically inspired models of behavior, and also inspire the study of Petri net variants computation: their operation attempts to imitate the func- suitable for the modeling of membrane system computationing of living cells. The computation in a membrane tions, [1, 2] system proceeds in distinct regions called membranes or compartments. The compartments allow computation with multisets: they accomplish transformations of their References contained multisets by various evolution rules. In the original symbol object model, the compartments are or- [1] Bogdan Aman, Péter Battyányi, Gabriel Ciobanu, ganized in a tree like structure and the rules account for György Vaszil: Local time membrane systems and the computational processes in the compartments in a time Petri nets. Theoretical Computer Science 805: parallel and distributed manner. Multisets of objects on 175-192 (2020) the left hand sides of rules are transformed to multisets [2] Péter Battyányi, György Vaszil: Description of on the right hand sides and these might also be placed membrane systems with time Petri nets: Promotto other regions of the system before the next computa- ers/inhibitors, membrane dissolution, and prioritional step begins. The computation proceeds until no ties. Journal of Membrane Computing 2(4): 341-354 more rule can further be applied in any of the regions, (2020) and the result is usually given by the objects of one or [3] Jetty Kleijn, Maciej Koutny: Petri Nets and Memmore designated output regions. In short, membrane sys- brane Computing. In G. Păun, G. Rozenberg, A. Satems consume, produce, and move objects around in the lomaa (editors) The Oxford Handbook of Membrane regions of their membrane structure. Computing Chapter 15, Oxford University Press,

The functioning membrane systems, described above, 2010: 389-412 might remind us of the behavior of place transition Petri [4] Jetty Kleijn, Maciej Koutny, Grzegorz Rozenberg: nets, since Petri net transitions also consume tokens from Towards a Petri Net Semantics for Membrane Systheir input places and produce new tokens at their out- tems. Workshop on Membrane Computing 2005: 292put places. If we establish a correspondence between 309 token distributions on the places of the net (markings) [5] Gheorghe Păun: Computing with Membranes. Jourand object distributions in the diferent regions of the P nal of Computer and System Sciences 61(1): 108-143 system (configurations), see [ 4], then the transitions of (2000) place/transition nets can naturally be described by multiset transformations in the membrane system. This is also true the other way around, the functioning of the membrane system based on the diferent kinds of objects and object evolution rules in diferent compartments can be described by the evolution of Petri net configurations (markings). See the handbook chapter [3] for more information.

In the presentation we look at these structural links between the two models in more detail. This approach