THOMPSON'S EXCHANGE MIXTURE SUPER RARE TOBACCO TIN.Early tax stamp of 1897 is 95% intact. One fourth pound size. Slip lid. Measures 3 in height X 3 1/4 in width.This tin is not in any tobacco tin book or list anywhere that we can find.HOMPSON'S EXCHANGE MIXTURE SUPER RARE TOBACCO TIN.Early tax stamp of 1897 is 95% intact. One fourth pound size. Slip lid. Measures 3 in height X 3 1/4 in width.
Nucleus, in biology, a specialized structure occurring in most cells (except bacteria and blue-green algae) and separated from the rest of the cell by a double layer, the nuclear membrane.
Introduction. Phosphofructokinase (PFK) is a glycolytic enzyme that catalyzes the irreversible transfer of a phosphate from ATP to fructose-6-phosphate: fructose-6-phosphate + ATP fructose-1,6-bisphosphate + ADP.In part because of the irreversible nature of this step in glycolysis, PFK is the key regulatory enzyme for glycolysis.When ATP levels are high in the cell, the cell no longer needs metabolic energy production to occur.In this case, PFK's activity is inhibited by allosteric regulation by ATP itself, closing the valve on the flow of carbohydrates through glycolysis.Recall that allosteric regulators bind to a different site on the enzyme than the active (catalytic) site.hen ATP levels are high in the cell, the cell no longer needs metabolic energy production to occur. In this case, PFK's activity is inhibited by allosteric regulation by ATP itself, closing the valve on the flow of carbohydrates through glycolysis.