Diabetes
Diabetes is a condition where blood glucose concentration cannot be controlled properly
TYPE I:
• Immune system attacks the B cells in the islets of langerhans so insulin cannot be
produced
• This results in hyperglycaemia (blood glucose levels rise after eating and stay at a high
level)
• Kidneys are unable to reabsorb the large amounts of glucose so some is excreted in the
urine
• As a result people with type I diabetes have to control their blood glucose concentration
by injecting themselves with insulin
• Insulin therapy has to be controlled as too much can cause hypoglycaemia
• Type I diabetics are insulin dependent
TYPE II:
• Appears later on in life
• Linked with obesity and family history of the condition
• Risk factors include lack of exercise, age and poor diet
• It can be caused by decreased insulin production or by glycoproteins on target cells
becoming unresponsive to insulin
• This can be controlled by diet manipulation and exercise
High concentrations of glucose in urine could indicate diabetes
Determining the concentration of a glucose solution (required practical 11)
• Colorimetry is used to determine the concentration of glucose in a sample of urine
• Use quantitative Benedict’s reagent
• When heated with glucose the initial blue colour is lost (red precipitate not produced)
• A colorimeter can be used to measure the light absorbance of the solution after the
quantitative Benedict’s test has been carried out
• The higher the concentration of glucose in the sample the more blue colours lost
therefore decreasing the absorbance of the solution
Making serial dilutions:
Diabetes is a condition where blood glucose concentration cannot be controlled properly
TYPE I:
• Immune system attacks the B cells in the islets of langerhans so insulin cannot be
produced
• This results in hyperglycaemia (blood glucose levels rise after eating and stay at a high
level)
• Kidneys are unable to reabsorb the large amounts of glucose so some is excreted in the
urine
• As a result people with type I diabetes have to control their blood glucose concentration
by injecting themselves with insulin
• Insulin therapy has to be controlled as too much can cause hypoglycaemia
• Type I diabetics are insulin dependent
TYPE II:
• Appears later on in life
• Linked with obesity and family history of the condition
• Risk factors include lack of exercise, age and poor diet
• It can be caused by decreased insulin production or by glycoproteins on target cells
becoming unresponsive to insulin
• This can be controlled by diet manipulation and exercise
High concentrations of glucose in urine could indicate diabetes
Determining the concentration of a glucose solution (required practical 11)
• Colorimetry is used to determine the concentration of glucose in a sample of urine
• Use quantitative Benedict’s reagent
• When heated with glucose the initial blue colour is lost (red precipitate not produced)
• A colorimeter can be used to measure the light absorbance of the solution after the
quantitative Benedict’s test has been carried out
• The higher the concentration of glucose in the sample the more blue colours lost
therefore decreasing the absorbance of the solution
Making serial dilutions:
