Scene at the Signing of the Constitution of the United States. The Constitutional Convention (also known as the Philadelphia Convention, the Federal Convention, or the Grand Convention at Philadelphia) took place from May 25 to September 17, 1787, in Philadelphia, Pennsylvania.
In living cells, WHAT serve as biological catalysts. Each acts on a specific substance called the enzyme's substrate and each catalyzes only one reaction. As catalysts, enzymes typically accelerate chemical reactions. The enzyme molecule has an active site, a region that will interact with a specific chemical substance.
1 The action of an Enzyme may be Intracellular (the Enzymes are attached to the cell membrane or are in the Cytoplasm, and reactions occur inside the cell) or Extracellular (Enzymes work outside cells, and their products may be absorbed into the cell). 2  Enzymes are also used in protection against Pathogens. Enzymes work by lowering the Activation Energy of a reaction. 2  The Activation Energy of a reaction is lowered by putting stress on the bonds within a molecule, or by holding molecules close together. 3  This increases the likelihood of a reaction, and so lowers the energy required to begin it.