How is blood glucose regulated by negative feedback regulation?

• By hormones• Made by endocrine gland-• Pancreas

Lets talk about pancreas…

• Because pancreas makes the hormones that regulate blood glucose

• Eat food• Blood glucose goes up• Q. What does blood do

with this glucose?• Delivers it to the cells.• How?• We need a hormone.

Pancreas makes the hormone insulin that helps to bring the blood glucose down

How does insulin work?

• It is released in the blood. It binds to the receptors on the cells and unlock the cells.

• Cells absorb glucose.• Why does glucose move from

the blood into the cells? • Because there is higher

concentration of glucose in the blood so it diffuses into cells where concentration is low

• It is called Diffusion

What does blood do with extra glucose?

• It takes it to liver and muscles

• They store it as GLYCOGEN (polysaccharide)

• How does liver take up glucose to store?

• Hormone insulin…• What did insulin help

accomplish?• It brought the blood

glucose down

• Some cells need more glucose because they are working more than others. So blood needs to carry some glucose all the time.

• What if blood glucose goes down too much?

• You have HYPOGLYCEMIA

How do you bring the blood glucose levels back up?

• Pancreas makes glucagon

• How does glucagon work?

• It fits the receptors on liver and muscles and signals them to release glucose by breaking down glycogen

Why does glucagon only give signal to liver and muscles, and not brain?

• Because only liver and muscles have the receptors for glucagon.

• Can you explain how receptors work?

• They fit with the signal because of their shape

In summary, how Pancreas regulates blood sugar?

• Which type of regulation is this?

• Negative feedback regulation

• Can you explain negative feedback regulation?

• If there is change in one direction, another change happens in the opposite direction

Which life function is accomplished by this regulation?• Homeostasis• Is the ability to

maintain a stable/constant internal environment

WHO makes hormones?