The incredible catalytic power of enzymes can perhaps best be appreciated by imagining how challenging life would be without jus
t one of the thousands of enzymes in the human body. For example, consider life without fructose-1,6-bisphosphatase, an enzyme in the gluconeogenesis pathway in liver and kidneys, which helps produce new glucose from the food we eat: Fructose-1,6-bisphosphate + H2O → Fructose-6-phosphate + Pi
The human brain requires glucose as its only energy source, and the typical brain consumes about 120. g (or 480. calories) of glucose daily. Ordinarily, two pieces of sausage pizza could provide more than enough potential glucose to feed the brain for a day. According to a national fast-food chain, two pieces of sausage pizza provide 1260 calories, 49.0 % of which is from fat. Fats cannot be converted to glucose in gluconeogenesis, so that leaves 615 calories potentially available for glucose synthesis. The first-order rate constant for the hydrolysis of fructose-1,6-bisphosphate in the absence of enzyme is 2.00×10-20 sec-1.Calculate how long it would take to provide enough glucose for one day of brain activity from two pleces of sausage pizza without the enzyme.
As the average kinetic energy increases, the particles move faster and collide more frequently per unit time and possess greater energy when they collide. Both of these factors increase the reaction rate. Hence the reaction rate of virtually all reactions increases with increasing temperature
There are three ways that scientists have proved that these sub-atomic particles exist. They are direct observation, indirect observation or inferred presence and predictions from theory or conjecture. Scientists in the 1800's were able to infer a lot about the sub-atomic world from chemistry.