The creation of new glucose is GLUCONEOGENESIS

A rise in blood glucose concentration:
1) receptors pick up that there is high glucose in the blood
2) the beta cells in the islets of Langerhans secrete insulin directly into the blood stream.
3) insulin increases the permeability of of cell membranes to glucose , so more glucose is absorbed.
4) Insulin also activates the condensation of glucose to glycogen in glycogenesis
5) insulin also increases the rate of respiration of glucose.
6) blood glucose decreases


A decrease in blood glucose concentration:
1) alpha cells of the islets of Langerhans secrete glucagon into the blood stream.
2) this activates the hydrolysis of stored glycogen to glucose . this is called glycogenolysis
3) blood glucose increases

Pancreas:
key organ in controlling blood glucse levels
cells are known as the islets of langerhaans, are endocrine function.
Alpha cells secrete: glucagon
beta cells secret: insulin

these hormones are secreted straight into the blood capillaries
they are antagonistic

Insulin is a hormone that decreases the level of glucose in the blood. Two effects of insulin are cells are more permeable to glucose, speeds up acquisition. it also activates enzymes stimulation the conversion of glucose to glycogen.
Its main target organs are the Pancreas, Liver, muscles.

Glucagon hormone that increase blood sugar, main effect is that it activates enzymes which are responsible for converting glycogen into glucose (glycogenolysis)

the brain only respires glucose

glycogenesis: the synthesis of glycogen from glucose under the influence of insulin

glycogenolysis: the breakdown of insoluble glycogen under the influence of glucagon to form glucose.
gluconeogenesis: the creation of glucose from non carb sources e.g. lipids/ fatty acids or protein.

test for glucose:
diabur strips, yellow= no glucose,
progressively darkgreen-blue= glucose present

Benedicts test:(less sophisticated)
not specific to glucose just for redcuing sugars
after heating for 3 mins a blue solution means no glucose.
a brick red means glucose