1. My roommate and I are both right because there are two ways in which a substrate binds on the active site of an enzyme. The model that I am talking about is called the lock and key model theory that states that an enzyme with an active site has a specific shape that can only fit a substrate with that specific shape. The substrate will then act like a key and the active site as the lock, so that when the substrate attaches to it becomes activated and allows for reactions to occur that ultimately lead to the formation of products. There is another model called the induced fit theory that makes my roommate correct as well because there is more than one way a substrate can bind. In the induced fit model theory, it states that when the correct substrate binds to the active site of an enzyme, it will respond to the binding of the substrate causing it to change the shape and conformation of it. 2. if K=1 then ?G? = 0 and is in equilibrium3. if K>1 then ?G? < 0 and is exergonic4. if K<1 then ?G? > 0 and is endergonic5. How is the overall free energy of a reaction useful for understanding enzyme function?The standard free energy of a reaction will let you know whether a reaction will be spontaneous. This is important because with this we are able to tell whether the reaction is exergonic or endergonic. If the delta G is negative the reaction will be spontaneous in other words exergonic. If the delta G is positive then the reaction will require you to put in energy and in other words endergonic. This is vital because if a reaction is endergonic it needs a little help of enzymes that will help move the reaction forward. The enzyme will help by bringing down the activation energy of the reaction down and will help create the transition state, which is through the binding of the enzyme through the substrate.6. Transition-state analogs are chemical compounds that resemble the structure of a transition state of a catalyzed reaction and are potent inhibitors of enzymes. These transition-state analogs are considered inhibitors because they will bind to the enzyme a lot tighter than a substrate will. The transition-state analogs mimic the transition state of a reaction but they do not allow the enzyme to be activated treating it as an inhibitor to the enzyme.7. The way in which enzymes help to facilitate the formation of the transition state is that they serve as catalysts that help by decreasing the free energy of activation of these chemical reactions. Enzymes speed up the reactions and help the formation of the transition-state by creating a pathway that allows the transition state to have its free energy lowered and allows products to be formed faster than an uncatalyzed reaction would. It does this by combining the substrate and the enzyme which then creates the transition-state pathway and its energy is lower than it would be without the enzymes. Since the activation energy is now lowered, more of these molecules are able to reach the transition-state and create more products in a shorter amount of time. This is also known as catalysis, which also stabilizes the transition state.8. In the concerted model it has allosteric proteins that have many and multiple subunit proteins and on them have substrate binding sites with effector located on each of the subunit, when the subunit is in the R form it can be stabilized by the binding of an effector molecule or substrate this ultimately helps stabilize all the subunits that are also in the R form. The concerted model is considered an “all-or-none” Model because all the protein subunits must be either in the T state form or in the R state form. In the sequential model when you do bind the substrate molecule or an effector molecule it helps to stabilize a subunit in the R state form, when you have a subunit that is bound it then influences the adjacent subunit and affects the stability and will ultimately be stabilized in the R state form because of the binding of a either an effector molecule or a substrate molecule and this model is not considered an “all or none” model because there can be forms of protein with 1 subunit, 2 subunit, or even more. 9. The Michaelis-Menten equation is V0 = Vmax(S/(S + KM))V0 is the reaction velocityVmax is the Maximum velocity. It is the maximum rate of enzyme catalysis when it is saturated with substrate S is the Substrate concentration KM Michaelis-menten constant it is the substrate concentration at ½ Vmax10. In competitive inhibition, it works by having the natural substrate compete. the more of the concentration of the inhibitor that is present, the more likely the probability that the enzyme will bind to the inhibitor rather than the substrate itself. In noncompetitive or mixed inhibition the inhibitor can bind on an enzyme that already has a substrate bound to it. These inhibitors work by inhibiting the enzyme activity directly. In uncompetitive inhibition, these inhibitors will be able to bind on a different area .of the substrate and can only bind to the ES complex. This inhibitor decreasing enzyme activity by inhibiting it.