The Endocrine System

The endocrine system is made up of many glands that secrete hormones into the bloodstream. The blood carries the hormones around the body and each hormone acts on a target organ, which produces an effect.

Compared to the nervous system, the effects of hormones are much slower, but the effects are more long-lasting.

StructureHormone produced
Pituitary glandMany hormones, including anti-diuretic hormone (ADH), follicle-stimulating hormone (FSH) and luteinising hormone (LH)
PancreasInsulin and glucagon
Thyroid glandThyroxine
Adrenal glandAdrenaline
OvaryOestrogen and progesterone

Pituitary Gland

The pituitary gland, located in the brain, is a ‘master gland’ that can secrete many hormones into the blood. These hormones act on other glands, causing other hormones to be released. So the pituitary gland can trigger a range of effects in the body.