Aims• To know that our bodies are controlled by hormones.• To understand that different hormones affect different parts of our bodies in different ways.
What is a hormone? • Hormones are chemical messengers used in the body by the endocrine system. • They co-ordinate our organs. • Hormones are produced by glands.
Hormone controls. • Hormones travel slower than nerve impulses but have a longer lasting effect. • They are excreted by the glands and travel in the blood. • Hormones stabilise the bodys internal environment and also have roles in growth and sexual development.
Hormone controls. • Hormones control: • Growth • Sexual development • Sugar levels • Mood • Metabolism • Can you think of any problems that can be caused by these not working?
Hormone Regulation • Hormones are regulated by negative feedback. • Regulation of blood sugar is a good example of this.
Insulin Control Brain senses high blood sugar Pancreas produces Insulin Glucose stored in liver as glycogen Low blood sugar sensed by brain Pancreas produces glucagon Liver releases stored glycogen as glucose into blood