, like a neurotransmitter, is a chemical messenger that must bind to a receptor in order to send their signal.
The
closely works with the hypothalamus and is known as the "master gland" because its hormones control ALL the other glands in the endocrine system.
The
releases hormones that regulate growth, metabolism, and appetite.
The
s sit atop the kidneys and secret hormones involved in stress response like epinephrine (adrenaline) and norepinephrine (noradrenaline).
The
secretes insulin and glucagon to regulate the body's blood sugar levels.
is a condition where people do not produce enough insulin and may need to artificially stimulate their insulin levels.
The
s are important in reproduction and regulate sexual motivation and behaviour. In men they are the testes (which produce androgens like testosterone), and in women they are the ovaries (which produce estrogens and progesterone).