Which of the following best describes hormonal messengers?

Hormonal messengers are biological substances produced by endocrine glands, and they play a crucial role in regulating various physiological functions in the body. The correct characterization is that they are released by glands and travel through the bloodstream. This method of transport allows hormones to reach distant targets throughout the body, enabling them to influence processes such as growth, metabolism, and mood regulation.

The bloodstream serves as the delivery system for these hormones, allowing them to target specific organs or tissues that possess the appropriate receptors. This ability to communicate over long distances distinguishes hormonal signaling from other forms of cellular communication, such as neurotransmission, which usually occurs locally and rapidly.

Additionally, hormones can indeed have both immediate and long-term effects on the body's functions, making them versatile in the way they influence health and behavior. The nature of hormonal action often includes gradual changes that can affect overall system functions, which adds to their complexity and significance in maintaining homeostasis.

This understanding highlights the fundamental role hormones play in health and behavior, contrasting with other options that mischaracterize the nature and function of hormonal messengers.