Glucose Metabolism Flashcards
___________ is an endocrine hormone secreted by the _______ cells of the islets of Langerhans in the ____________.
Insulin
Beta
Pancreas
What is the principal function of insulin?
To assist the transport of glucose across the cellular membrane
What is hypoglycemia?
Low blood sugar
What causes hypoglycemia (in terms of insulin)?
Too much insulin (causes decrease in blood sugar)
What is hyperglycemia and what causes it?
High blood sugar
Too little insulin (not enough sugar entering cells)
What is the normal concentration for blood glucose?
60 mg/dl to 140 mg/dl
What disease can be caused by a lack of insulin?
Diabetes mellitus
A lack of insulin can cause diabetes mellitus. This fact can be demonstrated by either removing the pancreas of an experimental animal (or _______________________) or destroying the beta cells of the islets of Langerhans with a chemical toxin like _____________, an inhibitor of beta cells.
Pancreatectomy
Alloxan
What are the typical symptoms of diabetes?
High blood glucose levels and excretion of glucose in the urine
Define glucosuria.
Urinary excretion of glucose
Glucosuria occurs when the concentration of blood glucose ____________ the threshold level for total ____________ by the ____________.
Exceeds
Reabsorption
Kidney
Increased osmolarity of urine can lead to excess water excretion or ___________ and excessive water intake or ________________.
Polyuria
Polydipsia
What are the three main characteristics of diabetes?
Glucosuria, polyuria, and polydispia
Diabetes mellitus received its name because the body of the diabetic was visualized as ____________ and ____________ out via the ____________ urine.
Melting
Flowing
Sweet-tasting
Why is the diabetic usually thin?
Because when insulin is deficient, the cells compensate by increasing their metabolism of fats and proteins
The increased metabolism of __________ releases into the blood large quantities of __________, which are intermediates of fat breakdown. They are excreted in the urine and have the easily recognizable odor of ____________. They are also _____________ and can lead to a ___________ in pH levels and _________________.
Fats Ketone bodies Acetone Acidic Drops Acidosis
What does hyperinsulinism cause?
Weakness, tremor, hunger, irritability
Insulin __________ can occur if blood glucose levels fall to very low levels.
Shock
What tests are used to diagnose diabetes?
Tests for urinary glucose levels, urinary ketone bodies, fasting blood glucose level, insulin sensitivity, and glucose tolerance
What is the glucose tolerance test?
It assays the ability of the body, notably the pancreas, to respond to an excess ingestion of glucose. The changes in blood glucose levels following such ingestion are markedly different in the normal and diabetic person
In the normal person, blood glucose levels rise from about _____ mg/dl to ______ mg/dl in one hour and then return to normal after a glucose tolerance test.
90
140
In the diabetic person, blood glucose levels rise from about ______ and ______ mg/dl to as high as ______ and then slowly fall to fasting diabetic levels after a glucose tolerance test.
120 and 160
300
What causes the diabetic’s abnormal response?
The inability of the pancreas to secrete additional insulin in response to elevated blood glucose levels
What does a glucometer do?
It measures blood glucose levels
Explain the basic procedure for the glucose metabolism lab.
- ) Fast
- ) Take fasting blood glucose levels with glucometer and/or complete fasting urinalysis via pH
- ) Drink a very sugary substance
- ) Repeat glucometer readings every 30 minutes
- ) At the end, an additional urinalysis may be performed
