Final answer:
The reproductive system is the least involved in maintaining homeostasis among the 11 major body systems.
Step-by-step explanation:
The least involved body system in maintaining homeostasis is the reproductive system. While all organ systems in the body work together to maintain homeostasis, the reproductive system is primarily focused on reproduction rather than regulating internal conditions.
For example, the reproductive system is responsible for producing and delivering sperm or eggs and supporting the growth and development of a fetus. Its main function is not directly related to maintaining a steady internal environment like other systems such as the respiratory or circulatory systems.
Therefore, the reproductive system can be considered the least involved in maintaining homeostasis among the 11 major body systems.