Who maintains the ecological balance?

Encounters with nature 6, textbook

9 control loops maintain homeostasis For living beings, it is necessary that certain internal states (eg body temperature, blood pressure, blood sugar level) remain in a functional framework. The regulation of these internal states is called homeostasis. A common mechanism in this context is negative feedback: if a variable to be controlled is not within the target range, corrective control mechanisms are initiated. These last until the target range is reached or exceeded again. (There is also a positive feedback: if the change in the controlled variable has an intensifying effect on oneself.) In small groups of animals, behaviors can also have a regulating function. In small groups of animals (herds, packs, swarms) there is coexistence more or less strictly regulated depending on the species. For example, wolves are known to have strict hierarchies that serve to avoid conflicts. They regulate the “rights” and “duties” within the group and ensure that a group as a whole has a better chance of survival. The control mechanisms for this purpose include: certain gestures, sounds or ritualized fights. In ecosystems, various control mechanisms maintain the biological balance. Animal and plant species that live together in a habitat (biotope) are part of an effective structure (biocenosis). This means that they act on each other as predators, food competitors, parasites, symbionts, etc. If this interaction is balanced over a longer period of time and does not only have one-sided advantages, then all species can survive in the habitat. This long-term condition is called ecological equilibrium and is based on ecological mechanisms of control and regulation (e.g. density regulation). Humans also intervene in the regulatory mechanisms in the earth's ecosystem on a global level and can upset an ecological balance, for example through energy policy - with serious consequences (e.g. global warming). Living systems (cells, organisms, communities) can react quickly and efficiently to changes, both external and internal. Mechanisms for regulation and control are necessary for this. Control mechanisms ensure that internal states remain within a functionally appropriate framework (target range) in spite of malfunctions. Control mechanisms enable adaptation to changed conditions, as they can actively change certain parameters independently of setpoints. Control and regulation In the course of the year, create your own "data collection" for the basic concept of control and regulation. Where did you come across it? Active yourself! Control loops • Homeostasis p. 86, 104 • Blood sugar level p. 105 • Female cycle p. 37 Social regulatory mechanisms • Ranking wolves p. 112 • Ranking chimpanzees p. 160 Ecological balance • Biocenosis p. 111 • Density regulation p. 112 • Energy policy p. 115 • Global warming p. 188 ff. For testing purposes only - property of the publisher öbv

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