Topic 11: Concepts Of Metabolism Flashcards
What’s is Gibbs free energy. Describe spontaneous reaction
Gibbs free energy is energy that is available to do work. A spontaneous reaction is when energy is released from a chemical reaction not energy is needed this it released. It breaking down not building making it catabolic.
This means we have an exergonic reaction where energy is released and the Reactants are higher than the products.
Compare and contrast endergonic and exergonic reaction. Provide an example of each.
Both endergonic and exergonic reactions occur in chemical reactions whether its inputing or releasing energy.
Endergonic: Is the input of energy. Its non spontaneous meaning it requires an input of energy. Its building meaning it’s an anabolic reaction. The Products will have a higher free energy than the reactants.
Exergonic: The releasing of energy. No input of energy needed meaning its spontaneous. It breaks down and its catabolic. The products will have less free energy than the reactants.
Draw a Gibbs free energy diagram for an endergonic and exergonic reaction.
Label the change in free energy and the activation energy.
Activation energy is the small amount of energy every chemical reaction needs.
Activation Energy Catalyzed: Will move at a faster rate by having low activation energy.
Un catalyzed Activation Energy: Will move at a slower rate by having high activation energy/
Describe the hydrolysis of ATP. What is the purpose of energy coupling?
The hydrolysis of ATP is when a powered ATP receives an input of H2O producing ADP and Pi and releasing energy. Now ADP and Pi require energy by the release of H2O ATP is produced back again.
Energy coupling occurs when the energy produces in one reaction is used to power another reaction.
What is an enzyme? Describe its role in a chemical reaction. How are enzymes regulated by the cell?
An enzyme is a protein that catalyzes chemical reactions and lowers activation energy.
A substrate binds to an enzyme causing a change in its shape and a change in the enzymes shape as well.
Enzymes are regulated by enzyme inhibition. Molecules or mechanisms can prevent substrates from binding or for the reaction to occur.
Competitive Inhibition: When an inhibitor competes with a substrate for the active site of the enzyme. When this occurs the substrate does not bind.
Non competitive inhibition: When an inhibition binds in a different site called allosteric site. Preventing a substrate form binding to the active site.
