Defense reactions refer to a set of physiological and behavioral responses that an organism exhibits when faced with a perceived threat. However, there are several alternative terms that can also be used to describe these responses. For example, some people may use the term "fight or flight" to describe the instinctual responses that occur during a stressful situation. Others might refer to these reactions as "self-protection behaviors," or "coping mechanisms." Additionally, "reactive behaviors," "self-defense mechanisms," and "survival responses" are all terms that are used to describe the same set of actions that are taken by an organism to protect itself against perceived threats. Ultimately, the choice of terminology used to describe defense reactions will depend on the context and audience being addressed.