CARBOHYDRATES

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Carbohydrates are the main source of energy for the body. Sources of carbohydrates are rice, bread, pasta, corn, and many more. When ingested they are reduced to monosaccharide by the body's biochemical processes.

The most predominant monosaccharide is glucose. Glucose- also known as dextrose- is the sugar tested in the clinical laboratory when a person requests for a blood sugar test.

Blood glucose levels are maintained in the body at 60-100 mg/dL and this level is maintained through the body's homeostatic ability.

When the glucose levels increase the primary hormone that decreases this levels is insulin. On the other hand, the primary hormone that increases glucose levels when it is below normal, is glucagon. Both of these hormones are produced by the pancreas in the beta and alpha cells of the Islets of Langerhans, respectively.

Since blood glucose levels are affected by diet through the food that we eat, fasting is required before a test is performed( except in cases of RBS - Random Blood Sugar).

Fasting hours for 8-12 hours is done prior to the extraction of blood.

In the colorimetric method of glucose determination, visit the link below for full information and example:
Bioassaysys.com