What is Glucose Metabolism ?
There are 4 main processes that involved in glucose metabolism :
i) Gluconeogenesis
- Process to produce/provide from pyruvate into glucose.
ii) Glycogenolysis
- Process to stimulate the conversion of glycogen into glucose.
- Catabolism process
iii) Glycolysis
- The process to break down the glucose (sugar) to form energy.
- Catabolism process.
- The end product are pyruvic acid and ATP.
iv) Glycogenesis
- The process to store the break down of glucose (sugar) when changed into glycogen.
- Anabolism process.
i) Gluconeogenesis
- Process to produce/provide from pyruvate into glucose.
ii) Glycogenolysis
- Process to stimulate the conversion of glycogen into glucose.
- Catabolism process
iii) Glycolysis
- The process to break down the glucose (sugar) to form energy.
- Catabolism process.
- The end product are pyruvic acid and ATP.
iv) Glycogenesis
- The process to store the break down of glucose (sugar) when changed into glycogen.
- Anabolism process.
*The pathway in the carbohydrate metabolism :Carbohydrate metabolism involved the small intestine where the monosaccharides are observed into the capillary blood. Concentration of glucose in blood are controlled by insulin, glucagon and epinephrine.
- When the concentration of glucose in blood is increase, insulin is secreted by the pancreas. - When the concentration of glucose in blood is decrease, glucagon and epinephrine are secreted to stimulate the conversion of glucagon into the glucose through glycogenolysis. - Because of little ATP that produced by glycolysis process, the reaction are then continue to pyruvic acids into acetyl-CoA, then to citric acid in the citric acid cycle. - Pyruvic also can be converted into lactic acid compared to acetyl CoA because of the strenuous muscle activities. When the muscle in the resting time, the lactic acids then will convert into pyruvic acid which then undergo the gluconeogenesis process. - The conversion of glucose into glycogen by glycogenolysis also could occur and because glucose is not needed on that time. * Glycolysis and Gluconeogenesis*- As we know, the gluconeogenesis occur when the glucose level in blood are low. Then, these substrate are needed to genesis new glucose:
1) Amino acids 2) Lactate 3) Glycerol 4) Pyruvate. - Gluconeogenesis require anabolic pathway to synthesize the formation of glucose from amino acids, lactate and glycerol which then it also need energy to break down pyruvate. |
* Important events in Glycolysis*- There are 4 important events that happen in glycolysis:
i) Substrate level phosphorylation which is the phosphate group from ATP are transferred to glucose. ii) 6C molecules of glucose is broken down with two 3C molecules. iii)2 electrons are transferred to the coenzyme NAD iv)The energy is in ATP form. - For glycolysis, the glucose is needed 2 molecules of pyruvate to convert into 2 ATP or NADP. - Energy is required in this process. Can glycolysis could not occur in our body?
Answer : YES !!! - If glycolysis could not occur, the level of glucose in the blood will at abnormally low level which then cause the hypoglycemia. How can this happen ? - This condition will happen when the person with diabetes take medicine too increase the insulin levels in the blood. Taking too much of medicine, skipping meals, eating less than normal or do exercise more than usual can cause the glucose level in the blood decrease. Because of that, hypoglycemia can happen. |