S4.5.4 For the adult
Hormones
Your heart pounds when you get a fright, and you still feel shaky a minute later. What is carrying that message?
What this chapter teaches
A hormone is a chemical made by a gland and carried in the blood to target organs. It is slower than a nerve impulse and its effect lasts longer. The pituitary, thyroid, adrenal glands, pancreas, ovaries and testes each release their own hormones.
Three questions to ask
There is no one right wording. Listen for the idea.
- How is a message sent by a hormone different from a message sent by a nerve?
- Why does a hormone affect only some organs, when the blood reaches all of them?
- Which glands can you name, and what does each one release?
After the chapter, the learner can
- Compare nerves and hormones by speed and how long effects last
- Name the main glands and the hormones they make
What they copy into their notebook
Hormones are chemicals made by glands, carried in the blood to target organs. Slower than nerves, but they last longer. Pituitary controls other glands. Thyroid: thyroxine. Adrenal glands: adrenaline. Pancreas: insulin and glucagon.