What chemical messengers that are produced and secreted by glands into the bloodstream where they travel to target cells?

The chemical messengers produced and secreted by glands into the bloodstream are called hormones. These hormones travel to target cells to regulate various physiological processes, including metabolism, growth, and mood. Examples include insulin, which regulates blood sugar levels, and cortisol, which helps manage stress responses. Hormones play a crucial role in maintaining homeostasis within the body.