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? _________________________________________________________________________________________________________

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

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

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

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.

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 2 hr 3 hr 4 hr 5 hr 6 hr 7hr 8 hr Time Meal eaten

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 2 hr 3 hr 4 hr 5 hr 6 hr 7hr 8 hr Meal eaten Time

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

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

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

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

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? __________________ ________________________________________________________________________________

Check for Understanding Why is it important to regulate the glucose blood level? _______________________________________________________________________________________________________________________________________________________________________________________________________________________