Hormonal Control (OCR Gateway GCSE Biology: Combined Science)

Revision Note

Test Yourself





The Endocrine System

  • A hormone is a chemical substance produced by a gland and carried by the blood, which alters the activity of one or more specific target organs i.e. they are chemicals which transmit information from one part of the organism to another and bring about a change
    • The glands that produce hormones in animals are known collectively as the endocrine system

The major endocrine glands in the body

Major endocrine glands of the body

Table of endocrine hormones


    • Endocrine glands have a good blood supply as when they make hormones they need to get them into the bloodstream (specifically the blood plasma) as soon as possible so they can travel around the body to the target organs to bring about the response
    • Hormones only affect cells with target receptors that the hormone can bind to.
      • These are either found on the cell membrane, or inside cells.
      • Receptors have to be complementary to hormones for there to be an effect.
    • The liver regulates levels of hormones in the blood; transforming or breaking down any that are in excess.

How hormones work

Only cells with complementary receptors can bind with and respond to the hormone

Hormones v's nervous impulses

  • Hormones are used to control functions that do not need instant responses
    • Compared to the nervous system the effects of hormones are slower but they act for longer

Table to compare responses of the nervous and endocrine system

Comparison of Nervous & Hormonal Control table

Exam Tip

You will come across hormones at various points throughout the course, so remember to refer back to what you have learnt here about hormonal action as it will help you understand their effects

You've read 0 of your 0 free revision notes

Get unlimited access

to absolutely everything:

  • Downloadable PDFs
  • Unlimited Revision Notes
  • Topic Questions
  • Past Papers
  • Model Answers
  • Videos (Maths and Science)

Join the 100,000+ Students that ❤️ Save My Exams

the (exam) results speak for themselves:

Did this page help you?


Author: Ruth

Ruth graduated from Sheffield University with a degree in Biology and went on to teach Science in London whilst also completing an MA in innovation in Education. With 10 years of teaching experience across the 3 key science disciplines, Ruth decided to set up a tutoring business to support students in her local area. Ruth has worked with several exam boards and loves to use her experience to produce educational materials which make the mark schemes accessible to all students.