ECA: Proteins and Enzymes: Directions: Work in your lab groups to answer the following questions, make sure each member of the group understands all the concepts. Any figures that are mentioned are found in the 8th Edition.
4.B.1. Interactions between molecules affect their structure and function.
a. Change in the structure of a molecular system results in a change of the function of the system.
b. The shape of enzymes, active sites, and interaction with specific molecules are essential for basic functioning of the enzyme.
Evidence of student learning is a demonstrated understanding of the following concepts:
1. For a simple chemical reaction to occur, the substrate must be complementary to the surface properties (shape and charge) of the active site. In other words, the substrate must fit into the enzymeís active site.
2. Cofactors and coenzymes can either enhance or inhibit enzyme function; this interaction relates to a structural change which alters the activity rate of the enzyme. The enzyme may only become active when all the appropriate cofactors or coenzymes are present and bound to the appropriate places (often the active site) of the enzyme.
3. No specific cofactors or coenzymes are within the scope of the course and exam.
c. Other molecules and the environment in which the enzyme acts can enhance or inhibit enzyme activity. In some systems a competitive inhibitor can bind reversibly to the active site, preventing substrate binding and changing the activity of the enzyme.
d. The change in function of an enzyme can be interpreted from a graphical representation of concentrations as a function of time. These representations demonstrate the relationship between an enzymeís activity and a competitive inhibitor.