What Are Hormones

Hormones are chemical messengers secreted by glands into the bloodstream, regulating various body processes. The pituitary gland, directed by the hypothalamus, plays a key role in hormone secretion. ADH helps regulate water content by acting on the kidneys, while adrenaline and cortisol manage stress responses. Hormones must reach target organs to elicit specific responses, similar to a postal system.

How do hormones reach their target organs and what is the significance of this process?

What happens during the fight or flight response in terms of hormone secretion?