The fundamental characteristics and behaviors of living organisms, viewed as complex, open systems. These systems are self-organizing and interact continuously with their environment, maintaining themselves through the flow of information, energy, and matter. Key principles include order, sensitivity or response to the environment, reproduction, adaptation, growth and development, homeostasis, energy processing, and evolution. These principles help to define what makes something “alive” and illustrate how living systems sustain and evolve over time. (Open Civics)