Now, Bifunctional simply means it has two different functions. In fact, the functions are essentially opposite functions and that's why we call it reciprocal. Now, allosteric means it contains special sites that combine allosteric effect or molecules that can basically affect the activity of that protein. So this is our bifunctional Alastairic enzyme and we have two different domains. This domain is known as the phosphorptokinase two domain, PFK two, and this domain is known as the fructose bisphosphatase II domain. So FBPA two now, because this ends in a kinase, you might expect that its function is to basically attach a phosphoryl group onto some type of molecule.