The system that works slowly by sending chemical messengers through the bloodstream is known as what?

The endocrine system is the correct choice because it is responsible for regulating various body functions through the release of hormones. These hormones act as chemical messengers that travel through the bloodstream to target organs and tissues, influencing processes such as metabolism, growth, and mood. The action of the endocrine system is generally slower compared to other systems, such as the nervous system, which has a more immediate effect by transmitting signals through neurons. This slower response is significant for processes that require longer-term regulation rather than quick reactions, making the endocrine system essential for maintaining homeostasis in the body.