When glucose is consumed in excess,the following reaction occurs.
The function of insulin is that it causes the cells to remove glucose from the circulatory system.
During glycolysis the action of hexokinase is controlled by the concentration of glucose-6-phosphate.The first steps of glycolysis are shown below. This is an example of feedback inhibition.
The electrons and hydrogen ions carried from the citric acid cycle by FADH2 and NADH ultimately end up in the following reaction which occurs in the matrix of the mitochondria.