The Endocrine System

Consists of a series of glands

All glands secrete hormones into the blood

--> spread through the body via the blood stream

Tissues have receptors specific to the hormones

Pituitary gland (master gland)

Thyroid gland: produces thyroxine

--> regulates rate of metabolism as well as growth and development

Adrenal Gland: releases adrenaline

Pancreas: produces insulin

--> regulates blood glucose concentration

Testes (males): produce testosterone and sperm

Ovaries (females): produce progesterone and oestrogen

 

Endocrine system works closely together with the nervous system

Hormones: chemicals released by glands or tissues

Glands secrete hormones directly into the blood

Each hormone only interacts with specific receptors on some cells to cause a specific response

Circulating hormones: travel around the body in the blood

Local hormones: act on neighbouring cells without entering the bloodstream

 

Gland

Location (description)

Hormones

Function of the hormone

Hypothalamus

Brain above pituitary gland

Dopamine, Growth Hormone, Oxytocin

Control center to maintain homeostasis

Pituitary Gland

Brain below the hypothalamus

Cortisol, growth hormone, pregnancy hormone

Controls other glands

Pineal Gland

Center of the brain

Melatonin, Serotonin

Regulates the sleep cycle

Thyroid Gland

Throat

Calcitonin

Controls metabolic rate, heart rate and digestion

Adrenal Gland

Above Kidneys

Adrenaline, cortisol, testosterone

Immune system/metabolism

Pancreas

Middle of the body

Insulin

Regulates blood sugar levels and the digestive system

Testes

Male reproductive organs

Testosterone

Promotes male secondary sexual characteristics and produces sperm

Ovaries

Female reproductive organs

Oestrogen and progesterone

Promotes female secondary sexual characteristics, produces eggs and role in the reproductive cycle