Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Hormones are chemical messengers produced by specialized glands in multicellular organisms. They travel through body fluids (such as blood) to target cells or organs, where they regulate various physiological processes and behaviors.
Related terms
Endocrine Glands: Endocrine glands are specialized organs that produce and release hormones directly into the bloodstream. Examples include the pituitary gland, thyroid gland, and adrenal glands.
Target Cells/Organs: Target cells or organs are specific cells or tissues that have receptors for particular hormones. They respond to hormone binding by carrying out specific actions or changes in function.
Feedback Mechanisms: Feedback mechanisms are regulatory processes that control hormone levels in the body. They involve either positive feedback (amplifying hormone production) or negative feedback (reducing hormone production) to maintain homeostasis.