---
title: "Hormone — AP Psychology Definition & Exam Guide"
description: "Hormones are chemical messengers your glands release into the bloodstream. Learn how they drive stress, motivation, sleep, and puberty on the AP Psych exam."
canonical: "https://fiveable.me/ap-psych-revised/key-terms/hormone"
type: "key-term"
subject: "AP Psychology"
---

# Hormone — AP Psychology Definition & Exam Guide

## Definition

Hormones are chemical messengers produced by various glands in the body that travel through the bloodstream to regulate specific functions or processes in different organs or tissues.

## Review

### Related Terms

- [Endocrine System](/ap-psych-revised/key-terms/endocrine-system): The endocrine system is a network of glands that produce and release hormones into the bloodstream.
- [Pituitary Gland](/ap-psych-revised/key-terms/pituitary-gland): The pituitary gland, also known as the "master gland," is a small pea-sized gland located at the base of the brain that controls the release of many hormones throughout the body.
- [Thyroid Hormones](/ap-psych-revised/key-terms/thyroid-hormones): These are hormones produced by the thyroid gland that regulate metabolism and energy levels.