Answer
Carbohydrates in the body exists principally in the forms glycogen and glucose.
Glycogen exists mainly in the skeletal muscles (325gm), and in liver 80-100gm. Blood carbohydrate is in the form of the sugar glucose. Erythrocytes/red blood cells (RBC), and neurons use glucose almost exclusively as their fuel source. It is very important that the oxygen transporting cells-- RBCs --and the cells of the CNS are always supplied with enough fuel, therefore blood glucose is carefully regulated, The two hormones responsible maintaining adequate levels of blood glucose are glucagon and insulin:
If blood glucose levels fall the body draws on its stored glycogen which it converts to glucose. If glycogen stores are depleted physical endurance is negatively affected. But the body will turn to the oxidation of fats in order to provide energy for survival.
Work Step by Step
The RDA for carbohydrates is 125-175 grams per day
The normal level of blood glucose in a normal healthy adult is about 70-110 mg/dL
If the blood glucose levels are too high, the pancreas responds by pouring out insulin; insulin instructs the cells of the body to take in more glucose, and this causes blood sugar levels to fall back to normal amounts. On the other hand, if blood sugar levels are too high( hyperglycemia), the hormone glucagon is released from the pancreas. It acts to tell the liver not to absorb too much sugar from the blood and to convert stored glycogen into glucose. These actions will elevate blood sugar levels back to normal amounts.
