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Blood Glucose. You have one minute to write down everything you can know about glucose and it’s uses. Blood glucose. Glucose test. Blood glucose control. Blood glucose is controlled by hormones. Hormones are: Always produced by glands and secreted directly into the blood
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Blood Glucose • You have one minute to write down everything you can know about glucose and it’s uses
Blood glucose • Glucose test
Blood glucose control • Blood glucose is controlled by hormones. • Hormones are: • Always produced by glands and secreted directly into the blood • Carried in the blood plasma to the cells on which they act which have receptors complementary to the hormone • Have widespread and long lasting effects
Blood Glucose Control • Pancreas is a large pale coloured gland • It produces enzymes (protease, lipase and amylase) • And Hormones (insulin and glucagon)
Blood Glucose Control • Most of the pancreas makes enzymes for digestion but scattered throughout these cells are hormone producing cells – islets of Langerhans
Blood glucose control • You DON’T need to know about DELTA cells (somatostatin, growth-hormone-inhibiting hormone)
Blood Glucose Control • Normal blood glucose is 90mg per 100cm3 of blood • Where does blood glucose come from?
Blood Glucose control • Directly from the diet • Break down of glycogen – GLYCOGENOLYSIS • GLUCONEOGENESIS – making glucose from sources other than carbohydrates, the liver can make glucose from glycerol and amino acids
Blood glucose control • To do…BLIND SEQUENCING • Tallest person is dealer • When you get your cards write your initials on the back of your card – don’t show them to anyone else! • In your groups of three number yourselves 1,2 or 3 • Number…go first. • Read what is on your card then put it face down on the table • Move clockwise around the group • Your task is to produce a feedback loop for blood glucose regulation WITHOUT looking at anyones cards but your own.
Blood Glucose Control • β cells detect a rise in blood glucose • β cells secrete insulin directly into the blood plasma • Insulin is a globular protein made up of 51 amino acids • Almost all body cells have glycoprotein receptors on their cell surface membrane that bind with insulin molecules
Blood glucose control • When insulin combines with the receptors, insulin brings about: • A change in the tertiary structure of glucose transport protein channels, causing them to change shape and open, allowing more glucose into the cells • An increase in the number of carrier molecules in the cell surface membrane • Activation of the enzymes that convert glucose to glycogen and fat
Blood Glucose Control • α cells of the islets of Langerhans detect a fall in blood glucose concentration • Α cells secrete glucagon directly into the blood plasma • Glucagon travels in the blood to receptors in the liver cells
Blood glucose control • Glucagon causes liver cells to: • Activate an enzyme that converts glycogen to glucose • Increases the conversion of amino acids and glycerol to glucose (gluconeogensis) • The amount of glucose in the blood returns to normal
Blood Glucose Control • Glucagon is not the only hormone that stimulates the break down of glycogen in the liver • Adrenaline also has an affect and it does this using the second messenger system (glucagon also uses this system!)
Second messenger model • Hormone (Adrenaline) is the 1st messenger – it binds to receptors on the cell-surface membrane of target cells (Liver) to form a hormone-receptor complex • The hormone receptor complex activates an enzyme inside of the plasma membrane • This enzyme acts on ATP • The enzyme produces cyclic AMP (removing two of the phosphate groups) cAMP • cAMP is the second messenger and activates other enzymes that carry out the breakdown of glycogen to glucose • Draw a series of diagrams to summarise this
Summary time • Draw a cartoon (with characters and everything) to show how blood glucose levels are regulated
Blood Glucose control • What can you remember from yesterdays lesson? • Draw a five minute poster to summarise it!
Diabetes • What can you remember about diabetes – write it on your post it note and stick it on the board. • Diabetes
diabetes • Diabetes is a condition where the homeostatic control of blood glucose breaks down • 2 million people in the UK suffer from diabetes and the numbers are growing – why?
diabetes • Home and Away • In your pair you have been given either TYPE I or TYPE II diabetes • Your job is to read through the information and SUMMARISE it for your partner.
Type I vs II diabetes • Draw a venn diagram to compare the different types of diabetes.
Diabetes • Blood glucose tests – lets test some different samples and see if you can spot: • The normal person • The person with Diabetes • The person with kidney disease • The person who is dehydrated.