In enzymes, some of these amino acids form a site in the structure that catalyzes the enzymatic reaction. This site, called the active site of the enzyme, has amino acids that bind specifically to the substrate molecule, also called a ligand (Fig. 2). In a similar manner, certain sites in cell receptor proteins bind to specific ligand molecules that the receptor recognizes.
When did France's second empire end? The Second Empire ended with the swift and catastrophic defeat of  France in the Franco-Prussian war of 1870. The war was engineered  by Bismarck with the idea that Germany â¦would be united.This  included the capture by the Prussians of the Napoleon III. Then the  proclamation at Versailles of the German Empire, the loss to France  of Alsace and Lorraine, and the proclamation of the Third Republic.
The Foundation of the Second Spanish Republic. The Second Republic was formed on April 14, 1931 after local elections returned anti-monarchist representatives in most cities and large towns. Although much of rural Spain elected pro-monarchist politicians, everyone, including King Alfonso XIII, knew that local caciques (local town bosses) controlled the vote. Realizing his perilous position King Alfonso XIII went quietly into exile leaving Spain a republic for the first time since 1874. Although the Second Republic was greeted with much popular enthusiasm, significant segments of society were wary of the new regime.