1. Hormonal Regulation of Carbohydrates

2. Hormones What are hormones? maintain homeostasis (jack)
chemical messenger (jady)
chemical produced at one part of the body in response to situation at another part of the body
insulin & glucagon – from the pancreas to regulate blood glucose level (bgl)

3. Islet of Langerhans
As blood goes through the pancreas, insulin or glucagon is released into the blood stream based on the b.g.l
Alpha-cells – glucagon
Beta-cells - insulin

4. Blood Glucose Level When B.G.L is high When B.G.L is low
Insulin is released (β)
body cells to take in glucose
Muscles and liver takes in glucose (why?)
muscle & liver cells use glucose to make glycogen for storage
Excess glucose is turned into fat (why?)
long-term storage of energy
When B.G.L is low
Glucagon is released (α)
Epinephrine and cortisol are released
Hydrolysis of glycogen
Glycogen – storage form of carbohydrates in animals
The release of insulin and glucagon is not an all-or-nothing situation. The relative concentrations of these two hormones in the blood determine the shift between energy storage and mobilization
Impaired glucose regulation: hyperglycemia and hypoglycemia

5. Insulin-Responsive Glucose Transporter
Glucose transporter – facilitated diffusion
Insulin responsive glucose transporters – requires insulin
Skeletal muscles temporarily take up glucose during exercise without insulin b/c muscle contraction “opens up” glucose transporter.
Brain and liver cells have glucose transporters that do not require insulin for the uptake of glucose

6. a lot more complex…

7. Insulin Promotes Energy Storage
Uptake of glucose into some cells
Glycogenesis: glucose  glycogen (reversible)
Glucose  fatty acids (irreversible)
Stimulate protein synthesis

8. Hypoglycemia – low glucose
Feel nauseated, dizzy, irritable, sleepy, etc
Too much insulin produced
Prolonged exercise
Reactive hypoglycemia
Fasting hypoglycemia

9. Glucagon Promotes Mobilization of Stored Energy
Glycogenolysis: glycogen  glucose
glucagon – liver to break up glycogen to release glucose into the blood for energy
epinephrine – muscle to break up glycogen to release glucose used by muscles
Gluconeogenesis: amino acids  glucose
liver glycogen lasts for about 24 hrs after that the body breaks down proteins for energy
Ketogenesis: fatty acids  ketones (acidic/toxic)
Liver glycogenolysis is stimulated by glucagon
Muscle glycogenolysis is stimulated by epinephrine
Gluconeogenesis is stimulated by both glucagon and epinephrine

10. Ketogenesis Fatty acids  ketones Occurs in the liver
Stimulated by glucagon
Energy usable by the brain, heart, muscles, and kidney
Accumulation of ketones  ketosis
Gluconeogenesis results in muscle loss and has its consequences (cardiac muscles).

11. Immediate Energy Source
Cortisol released in response to a “fight or flight” situation
Decrease glucose uptake (exept for the brain)
Stimulate glycogenolysis & gluconeogenesis

12. Concept Map Groups of 2 or 3 Blood glucose level
Scott & Tommy / Isabelle & Shirley
Chemical reactions in b.g.l. regulation
Joseph & jack / lily & Noelle
Hormones involved in b.g.l. regulation
Jady & Leo & George
Theo & Emily & Maggie