Endocrine System Overview

An organ whose cells secrete materials into the body via duct-like structures.

A bodily tube through which secretions from glands are transported.

Ductless glands that secrete hormones directly into the bloodstream or surrounding fluids.

Chemical messengers that carry instructions to cells to change their activities.

Cells that have specific receptors for a specific hormone, allowing that hormone to bind and exert its effects.

The system that coordinates the body's sources of hormones, keeping it functioning properly.

A gland that serves as both an endocrine and exocrine gland.

A gland located at the base of the brain. It produces hormones that control the activity of other endocrine glands.

A pea-sized gland located in the center of the skull, below the hypothalamus. It is often called the 'master gland' because its hormones control many endocrine functions.

The part of the pituitary gland that secretes ACTH, GH, MSH, TSH, FSH, LH and prolactin.

The part of the pituitary gland that secretes antidiuretic hormone (ADH) and oxytocin.

A hormone that stimulates the adrenal glands to produce steroid hormones.

A hormone responsible for stimulating the growth of bones and tissues.

A hormone that regulates melanin production.

A hormone that stimulates the thyroid gland to produce thyroid hormone.

Hormones that control sexual function and production of sex hormones.

A hormone that stimulates milk production in women.

A hormone that controls water loss in the kidneys.

A hormone that stimulates milk production and uterine contractions during childbirth.

A gland located just under the larynx. It secretes T3, T4 and calcitonin, hormones that regulate metabolism, heart rate, blood pressure and development.

A condition caused by excessive production of T3 and T4, leading to high blood pressure, irritability, sweating and weight loss.

A condition caused by insufficient production of T3 and T4, leading to weight gain, lethargy and intolerance to cold.

A hormone produced by the thyroid gland that lowers blood calcium levels.

Four tiny glands embedded on the surface of the thyroid. They release parathyroid hormone, which regulates blood calcium levels.

A gland found behind the breastbone that is responsible for developing the body's immune defense system.

Two glands located on top of the kidneys. Each has an outer cortex and inner medulla that secrete different hormones.

The outer layer of the adrenal gland that secretes corticosteroids, which regulate metabolism, electrolyte balance, and stress response.

The inner layer of the adrenal gland that produces adrenaline, which plays a role in short-term stress response.

A hormone produced by the pancreas that regulates blood sugar levels by helping cells absorb sugar and turning excess sugar into glycogen.

A hormone produced by the pancreas that increases blood sugar levels by speeding up the conversion of glycogen into sugar.

The human reproductive organs, including testes and ovaries, which produce sex hormones.

A male reproductive organ that produces testosterone and sperm.

A hormone produced by the testes responsible for male secondary sexual characteristics.

Female reproductive organs that produce estrogen and progesterone.

A hormone produced by the ovaries responsible for female sexual development.

A hormone produced by the ovaries responsible for regulating the menstrual cycle and pregnancy.

A gland located near the thalamus of the brain that produces melatonin, which regulates body rhythms and sleep patterns.