1. Aim How does diabetes lead to a failure of homeostasis?

2. Glucose Glucose is a simple sugar Bonding glucose molecules together makes a starch which is a complex sugar

3. Insulin Insulin is a hormone secreted (released) by the pancreas to control blood sugar levels The pancreas is an organ located behind the stomach Pancreas

4. Diabetes Diabetes is a disease where the body is unable to produce enough insulin to maintain normal levels of sugar in the blood

5. Symptoms of high blood sugar Patient with high sugar levels usually feel tired and thirsty. Some experience cramps and feel weak These patients can go into shock and die if they do not get a shot of insulin

6. Two types of diabetes Type 1- Develops in children before the age of 15. Patient can not produce enough insulin Type 2- Develops in people after the age of 30. Patient has a bad diet and eats to much sugar

7. What could cause diabetes? 1.Person not producing enough insulin (type 1) 2.The target cell cannot receive signal because of a defective - Receptor molecule - Hormone 3. Poor diet- the person consumes to much sugar (type 2)

8. Hormone and Receptor molecule must fit in order to work Receptor molecule Hormone (Insulin) Pancreas Gland

9. Sending Signals What are the primary agents that the brain or a gland uses to communicate with other cells? Hormones Neurotransmitters (Nerve chemicals)

10. Failure of hormone to work means either the 1.Hormone is not produced 2.Receptor molecule is the wrong shape 3.The hormone is the wrong shape

11. Pancreas releasing insulin to maintain sugar levels is an example of a feedback mechanism When sugar levels rise the brain detects rise, then sends a signal to pancreas to release insulin. When sugar levels are normal pancreas stops secreting insulin Feedback mechanism

12. 1. The ability of the human body to keep blood-sugar levels within a fairly narrow range, despite the intake of meals high in carbohydrates, is an example of 1.active transport 2.genetic recombination 3.homeostasis 4.digestion

13. 2. The diagram shows the interaction between blood sugar levels and pancreatic activity. This process is an example of 1.a feedback mechanism maintaining homeostasis 2.an immune system responding to prevent disease 3.the digestion of sugar by insulin 4.the hormonal regulation of gamete production

14. 3. Feedback mechanisms are best described as processes that help 1.reduce hormone levels to below normal in the blood 2.destroy hormones in the blood 3.directly control muscle contraction in the leg 4.keep body conditions near a normal, steady state

15. The diagram below shows a biological process. Explain why the hormones attach to the target cell and not to other cells in the diagram The target cell has the receptor molecule with the specific shape that the hormone will fit