HormonesHormones

AimsAims• 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?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.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 body's internal environment and also have roles in growth and sexual development.

Hormone controls.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?

Growth hormone problems?!Growth hormone problems?!

Endocrine glands.Endocrine glands.

1)Pineal gland 2)Pituitary gland 3)Thyroid gland 4)Thymus 5)Adrenal gland 6)Pancreas 7)Ovary 8)Testis

Hormone RegulationHormone Regulation• Hormones are

regulated by negative feedback.

• Regulation of blood sugar is a good example of this.

Insulin ControlInsulin ControlBrain 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