Hormones are chemical substances which are produced in one part of an organism which have effect on another part. Below are the main hormones:
- Natural growth hormone, auxin is responsible for phototropism.
- Plant hormones are also used artificially for rooting.
- Rooting powder is put onto cuttings to make them root quicker.
- Produced in endocrine glands which pass hormones directly into the blood where they are distributed to
different parts of the body.
- The Pancreas produces insulin.
- Situated at the top of the kidneys.
- Produces adrenaline, the hormone produced when you are scared or excited.
- Adrenaline stimulates faster breathing, increased heart rate, more glucose and widening of blood vessels so more oxygen can be transported to the parts of the body that need it
- Produce sex hormones.
- Oestrogen from the ovary to cause secondary sexual characteristics and menstrual cycle.
- Testosterone from testes causes male secondary sexual characteristics.