Hormones and the endocrine system What exactly are hormones? What effect do hormones have on the body? To understand hormones you need to know about the endocrine system and how it works.

The endocrine system The endocrine system coordinates the body’s organs so that they work together. The endocrine system is based on the production of chemical messengers called hormones. Hormones are produced by glands (endocrine glands) in different parts of the body. These chemical messengers are produced in very small quantities and are transported in the blood. Hormones control body processes that require several organs of the body to interact for a combined effect.

What do hormones do? Hormones travel slower than nervous impulses but cause longer-lasting effects. They are delivered to all parts of the body but can have local effects. Hormones are used to stabilize the body’s internal environment through homeostasis and also coordinate longer-term processes such as growth and sexual development. Over- or under-activity of some endocrine glands can cause functional disorders such as diabetes.

Which body system?

Match hormones to glands

Endocrine glands and Hormones Copy the following table and complete with as much info as you can. Gland Hormones Use in body Thyroid Adrenal Pancreas Pituitary Ovaries Testes

Endocrine glands – thyroid Produces the hormone thyroxine: Regulates rate of metabolism. Excess causes hyperactivity. Deficiency causes weight gain and sluggishness. thyroid

Endocrine glands – adrenal glands Produce the hormone adrenalin. Adrenaline causes the ‘fight or flight’ response resulting in: Increased heart rate and breathing rate. Blood diverted to the muscles. Increased respiration to increase the amount of glucose in the blood. adrenal glands

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Match hormones to glands