Final answer:
Living organisms have the ability to maintain a stable internal environment in the presence of a changing external environment. This is called homeostasis.
Step-by-step explanation:
One characteristic property of living organisms is the ability to maintain a fairly stable internal environment in the presence of a changing external environment. This is called homeostasis. Homeostasis is the process by which living things keep their internal conditions relatively constant, regardless of the external conditions. For example, humans are capable of maintaining a stable internal body temperature even when the air temperature is below freezing. This is achieved through mechanisms such as shivering and other means to generate heat and maintain the body temperature.