A substance produced in one part of the body that causes action in another.

The definition of hormone:

Substances produced in one part of the body that cause action in another.

Hormones are only similar by definition. It’s a functional definition, not a reflection of anything about them physically or chemically. They are very different from one-another.

Example Hormones

  • Insulin is a hormone made in the pancreases that causes your blood sugar to change
  • Testosterone is the hormone of desire, amongst other things
  • Noradrenaline and Adrenaline are hormones that do basically the same thing as each other
  • Dopamine is a hormone that causes motivation

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