NOTE BEFORE YOU BEGIN: Normally, I recommend that you try to complete a study guide on your own before looking at the answer key. But this study guide is a little different. This time, I want you to try answering a question on your own, then looking it up in your textbook if necessary. After you have made your best attempt to answer one question, check the answer key before moving on to the next question.
It is important to complete this study guide in that way because each question builds on the information you learned in the previous questions. That makes it necessary to make sure you have a correct understanding of each answer before you can try to answer the next question.
1) Define and describe the normal roles of glucose, insulin, glucagon, and glycogen in a healthy person. Make sure to mention the affect that each one has on blood glucose levels.
- Glucose: Basically, sugar. Almost every cell in your body uses it as fuel, and needs it to survive. You get it from eating food. It increases your blood glucose level (duh!).
- Insulin: This is the “moving truck” that carries the glucose out of the blood stream and into the cells of the body that need it. The pancreas secretes insulin when blood sugar levels get too high. This allows for more of the sugar that is in the blood stream to now enter the cells, thus decreasing blood sugar level.
- Glucagon: This is a hormone released by the Pancreas when blood sugars get too low. It travels to the liver, and tells the liver to start turning Glycogen into glucose. Glucagon causes blood glucose levels to increase.
- Glycogen: When the body has extra glucose, it is turned into Glycogen and stored in the liver. When the liver gets a message from the Pancreas (via the hormone, Glucagon) it changes the Glycogen back into glucose, and releases the glucose into the blood. This process increases your blood sugar levels.
2) Okay, now tell me a little more about insulin in a healthy person! How often is it released? What exactly does it do in the body? Hint: It’s not enough to say “it helps the body use glucose.” HOW does it do that? What is it doing on a cellular level? If you were following a molecule of insulin through someone’s body, what would you see it doing? You may need to revisit your A&P for this one! But will be worth the effort because this is such an important concept, that there’s no point in studying Diabetes unless you understand it.
Insulin is released by the pancreas continuously in small amounts throughout the day. This is known as the basal rate. (Have trouble remembering that? Just think about it as the base rate.)
When you eat, the food gets digested and some of it is turned into glucose and enters the blood stream. This causes the pancreas to release a shot of extra insulin, called a bolus. The pancreas is giving your body a one-time bolus of extra insulin in response to the food you’ve eaten. (This word “bolus” should be familiar to you, because we also use it when talking about giving patients a one-time “fluid-bolus.” Look it up right now if you’re not sure what it means.) Once the insulin is released by the pancreas, it enters the blood stream.
THIS NEXT PART IS IMPORTANT!!
Once the insulin is in the blood, it goes to a cell and MOVES GLUCOSE OUT OF THE BLOOD AND INTO THAT CELL. Do you get that? Make sure to take a moment and think about it. Insulin does not “use up” glucose, it is simply the “moving van” that gets glucose from point A (the blood) to point B (inside the cell).
3) So just about everyone knows that having Diabetes Mellitus means that there is a problem with insulin. But there are actually two possible insulin problems you can have. Using the information you learned in question number 2 (and probably referring to your Med-Surg textbook), what are the two ways that the body can have a problem with insulin?
1. The pancreas make LITTLE TO NO insulin
a. This means there is not much, if any, insulin available to move glucose into cells
2. The cells are LESS SENSITIVE to the insulin that is being produced
a. This means that even though there might be plenty of insulin around, the insulin has a more difficult time moving the glucose into the cells.
4) What is the difference between Type I and Type II Diabetes? Which of the 2 problems with insulin do you think each Type has?
Type I: Makes little to no insulin, so the glucose has no way to get into the cell.
Type II: Could be due to both problems! It is usually a combination of the pancreas making less (but usually some) insulin. And also the cells are less sensitive, so the insulin has a more difficult time getting glucose into them.
Extra Info: Although many cells in the body require insulin in order to get their glucose, there are a few cell types that do not. These cells are able to take glucose into themselves without the help of insulin. What are the two primary cell types that require insulin, and the three primary cell types that do not?
- Need insulin:
- Skeletal muscle (voluntary control muscle)
- Adipose tissue (fat cells)
- Do NOT Need insulin:
- Brain cells
- Liver cells
- Blood cells