1. Unit 3: Homeostasis Topic: Glucose Regulation
Aim: How does your body regulate glucose level in the blood stream?
Quick Review: (let’s see if you remember)
Why is glucose important?
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2. Controlling Glucose levels
Your cells also need an exact level of glucose in the blood.
Glucose moves into the cells for cellular respiration
Excess glucose gets turned into glycogen in the liver
This is regulated by 2 hormones (chemicals) from the pancreas called:
Insulin
Glucagon

3. What happens if you have too much glucose in the blood due to a big meal you just had a few hours ago?
If there is too much glucose in the blood, Insulin converts some of it to glycogen the rest moves into the cells for use in cellular respiration.
Glycogen
Insulin
Too much Glucose in the blood

4. What happens if you have too little glucose in the blood because you haven’t been eating for the last 8-10 hours?
If there is not enough glucose in the blood, Glucagon converts some glycogen into glucose.
Glycogen
Glucagon
Too little Glucose in the blood

5. Diabetes: What causes diabetes?
Some people do not produce enough insulin.
When they eat food, the glucose levels in their blood cannot be reduced.
This condition is known as DIABETES.
Diabetics sometimes have to inject insulin into their blood. They have to be careful of their diet.

6. Glucose levels rise after a meal.
Glucose level in non-diabetic people
Glucose levels rise after a meal.
Insulin is produced and glucose levels fall to normal again.
Glucose
Concentration
Normal
1 hr hr hr hr hr hr hr hr
Time
Meal eaten

7. Meal eaten Glucose levels rise after a meal. Diabetic
Glucose level in diabetic people
Glucose levels rise after a meal.
Glucose
Concentration
Diabetic
Insulin is not produced so glucose levels stay high
1 hr hr hr hr hr hr hr hr
Meal eaten
Time

8. What would happen if your body does not produce enough insulin?
But there is no insulin to convert it into glycogen.
Glycogen
Insulin
The glucose in the blood increases.
Glucose concentration rises to dangerous levels.
Glucose in the blood

9. Blood Glucose Feedback Mechanism
Pancreas produces Insulin
Glucose into cells
Out of blood
Blood glucose increases Homeostasis Blood glucose decreases
( High ) (Low)
Glucose out of cells
Into blood
Pancreas produces Glucagon

10. Feedback: Maintaining Homeostasis
Balancing glucose levels in blood
cells take up glucose from blood
depress appetite
pancreas
insulin
liver takes up glucose for storage
liver releases glucose to blood
pancreas
stimulate hunger
glucagon

11. Regents Questions
During a race, the body temperature of a runner increases. The runner responds by perspiring, which lowers body temperature. This process is an example of
1.  maintenance of homeostasis
2. an antigen-antibody reaction
3. an acquired characteristic
4. environmental factors affecting phenotype

12. Check for Understanding
Which two hormones work together to regulate glucose level in your blood? _______________ and _______________
Which hormone is released when too much glucose is in your blood? ____________
Which hormone is released when too little glucose is in your blood?____________
What happens to glucose level in your blood if your body doesn’t produce enough insulin? __________________
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13. Check for Understanding
Why is it important to regulate the glucose blood level? _______________________________________________________________________________________________________________________________________________________________________________________________________________________