1. The Endocrine System Hormones = chemicals that are used to pass information around the body – (In the NS it was electrical signals; now it’s chemical signals) Endocrine Glands = organs that make and secrete the hormones Blood Capillaries = run through the gland and pick up the secreted hormones, then carry them through the bloodstream

2. Hormones Hormones travel all through the body (in blood), but only affect target organs. Insulin’s target organ is the liver – (but it’s made and secreted by the pancreas!) Hormones eventually get broken down by enzymes and excreted by the kidneys.

3. Endocrine Glands

4. Fight or Flight

5. Adrenaline Adrenaline = a hormone that increases your metabolic rate – Prepares your body for “fight or flight” Comes from the adrenal gland – Just above your kidneys Your brain sends a nerve signal to adrenal glands, stimulating them to secrete adrenaline into the blood.

6. Adrenal Glands

7. Adrenaline’s Functions Increases heart rate Increases blood glucose – (T.O. = Liver) Restricts blood to digestive system; increases blood to muscles – (T.O. = Arteries/arterioles) Increases width of lung passages – (T.O. = Bronchii/bronchioles)

13. Adrenaline… What is its function? What endocrine gland does it come from? What is its target organ?

14. Let’s Compare… Nervous SystemEndocrine System Type of Signal Speed of Signal Where the Signal Travels Where the Signal is Delivered How Long the Signal Lasts

15. Let’s Compare… Nervous SystemEndocrine System Type of SignalElectricalChemical Speed of Signal Where the Signal Travels Where the Signal is Delivered How Long the Signal Lasts

16. Let’s Compare… Nervous SystemEndocrine System Type of SignalElectricalChemical Speed of Signalseveral meters per second~ speed of blood Where the Signal Travels Where the Signal is Delivered How Long the Signal Lasts

17. Let’s Compare… Nervous SystemEndocrine System Type of SignalElectricalChemical Speed of Signalseveral meters per second~ speed of blood Where the Signal TravelsIn neurons and nervesIn blood vessels Where the Signal is Delivered How Long the Signal Lasts

18. Let’s Compare… Nervous SystemEndocrine System Type of SignalElectricalChemical Speed of Signalseveral meters per second~ speed of blood Where the Signal TravelsIn neurons and nervesIn blood vessels Where the Signal is Delivered To a specific part of the body Throughout the body (but only affects T.O.’s) How Long the Signal Lasts

19. Let’s Compare… Nervous SystemEndocrine System Type of SignalElectricalChemical Speed of Signalseveral meters per second~ speed of blood Where the Signal TravelsIn neurons and nervesIn blood vessels Where the Signal is Delivered To a specific part of the body Throughout the body (but only affects T.O.’s) How Long the Signal LastsSeconds or lessMinutes/Hours/Days