Which of the following is not characteristic of the adaptive immune system? a. It is specific for a given organ. b. It is antigen -specific. D c. It has memory. d. It is systemic.

The correct answer is a. It is specific for a given organ. The adaptive immune system is characterized by its ability to recognize and target specific pathogens or foreign substances, rather than being specific to a particular organ. It is antigen-specific, meaning it can recognize and respond to specific antigens present on pathogens or foreign substances. It also has memory, allowing it to mount a faster and more effective response upon subsequent exposures to the same pathogen. Additionally, it is systemic, meaning it operates throughout the body rather than being localized to a specific area.