Hormones Cambridge IGCSE Co-ordinated Sciences (Double Award) revision

Not started

Learn it

In plain words

Not every message in the body goes by nerve. Some are sent as chemicals released into the blood by glands. They travel everywhere but only affect the organs built to respond. They're slower than nerves, and their effects last longer.

Three things to know

  1. A hormone is a chemical made by a gland and carried in the blood, which changes the activity of one or more target organs.
  2. Adrenaline (adrenal glands) prepares the body for action: faster heart and breathing, wider pupils. Insulin (pancreas) lowers blood glucose. Testosterone (testes) and oestrogen (ovaries) are the sex hormones.
  3. Compared with nerves, hormones are slower to act, travel in the blood rather than along neurones, and have effects that last longer.

Tips and tricks

  • The definition has three parts: made by a gland, carried by the blood, affects a target organ.
  • Adrenaline is "fight or flight": everything it does gets more oxygen and glucose to the muscles.
5 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

Hormones: 5 questions and answers

These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.

  1. How do hormones travel round the body?
    • along nerves
    • in the blood (the answer)
    • through the gut
    • in the lymph only

    They are released into the blood by glands.

  2. Which gland makes insulin?
    • adrenal gland
    • thyroid
    • pancreas (the answer)
    • ovary

    Insulin lowers the blood glucose concentration.

  3. Which hormone is released when you are frightened?
    • insulin
    • adrenaline (the answer)
    • oestrogen
    • ADH

    It prepares the body for "fight or flight".

  4. Which statement about hormones is correct?
    • They act faster than nerves.
    • Their effects usually last longer than those of nerves. (the answer)
    • They are electrical signals.
    • They are carried by neurones.

    They are slower to act but longer-lasting.

  5. Where is testosterone made?
    • ovaries
    • testes (the answer)
    • pancreas
    • pituitary

    It causes the changes in boys at puberty.

Things you can type

Or go straight to

Or browse a shelf