# Shared Flashcard Set

## Details

Biochem 38-39 Bioenergetics
Biochem, bioenergetics, thermodynamics
22
Biochemistry
Professional
09/21/2010

## Additional Biochemistry Flashcards

Term
 1. What is thermodynamics
Definition
 Laws and principles that describe the interchange between Heat Energy Matter
Term
 2. What is enthalpy? When does it occur? Give examples
Definition
 Enthalpy is the change in heat (∆H). -∆H = Heat is lost by a system This is Favorable and Spontaneous Ex- Forming weak interactions during protein folding +∆H = Heat is gained by a system This is Unfavorable and Nonspontaneous Ex- Breaking weak interactions during protein folding
Term
 3. What is entropy?
Definition
 Entropy (S) is a measure of disorder -∆S = System is more Ordered  This is Unfavorable and Nonspontaneous +∆S = System is more Disordered This is Favorable and Spontaneous
Term
 4. What is Free Energy?
Definition
 Free Energy (∆G) Tells how much energy is available for work. It is dependent of ∆H and ∆S Allows you to assess Reaction Spontaneity -∆G is Spontaneous (Favors Products) +∆G is Nonspontaneous (Favors Reactants)
Term
 5. What happens to a reaction (A + B = C + D) when 1) ∆G = 0, 2) ∆G < 0, 3) ∆G > 0
Definition
 A + B = C + D When ∆G = 0 the reaction is at equilibrium When ∆G < 0, the reaction favors the Products (↑ C+D). Spontaneous When ∆G > 0, the reaction favors the Reactants (↑ A+B). Non-spontaneous
Term
 7. Relationship between ΔG & Keq for the reaction A + B = C + D
Definition
 ΔG = 0 at Equilibrium (no net change in [A], [B], [C], [D]) If ΔG < 0 (-ΔG) then ln Keq > 1 [C] and [D] Favored If ΔG > 0 (+ΔG) then ln Keq < 1 [A] and [B] Favored
Term
 8.1. What are High Energy Biomolecules
Definition
 1. Energy shuttles that move energy to reactions that need it
Term
 9. What 2 classes of biomolecules serve as High Energy Biomolecules (AKA Energy Transfer Molecules)?
Definition
 Reduced Coenzymes (NADH, FADH2). AKA: Electron Carriers High-energy Phosphate Compounds (ATP, GTP)
Term
 8.2. How are High Energy Biomolecules used in life
Definition
 Many energy requiring (+ΔG) reactions must occur to sustain life Cells couple highly favorable reactions (Large -ΔG) to energy requiring reactions (+ΔG) to force the +ΔG reaction forward Cells use High Energy Biomolecules to couple these reactions Energy liberated from the high energy biomoleule breakdown (-ΔG) is harnessed and used to drive the energetically unfavorable (+ΔG) reaction
Term
 10. Order the High Energy Phosphate Compounds in order from greatest to least free energy
Definition
 Greatest Free Energy PEP 1,3-BPG  ATP UDP-glucose Acetyl CoA Glucose 6-Phosphate Lowest Free Energy
Term
 11.1 Why is ATP considered the energy currency of the cell   11.2 How is ATP stable with its high energy capacity
Definition
 11.1 Because it is intermediate in terms of available free energy. It is easily formed and easily used   11.2 Because it has such a high Energy of Activation. ATP can't spontaneously convert to ADP because of its high Energy of Activation. However, an enzyme can catalyze this reaction easily
Term
 How is ATP formed?
Definition
 Molecules are made from molecules that have more free energy   PEP and 1,3-BPG are created in the course of glucose breakdown. The energy from these molecules is transfered (in combination with a phosphate) to ADP to form ATP
Term
 12.1. Describe the high energy bonds in ATP
Definition
 12.1. Bonds between phosphate groups in ATP are called phosphoanhydride bonds. When these bonds are hydrolyzed, energy is released because the products of the reaction (ADP and phosphate (Pi)) are more stable than the reactants (ATP and H2O)
Term
 13.1. What has phosphoric anhydride linkages?   13.2. What has phosphoric-carboxylic anhydride linkages?   13.3. What happens to phosphoric-carboxylic anhydride bonds
Definition
 13.1. ATP   13.2. Acetyl Phosphate and 1,3-BPG   13.3. They are hydrolyzed and acetate comes off
Term
 12.2. What reactions can ATP participate in
Definition
 ATP can transfer energy to enzymes (that then do work) ATP can activate other molecules (of lower energy phosphate compounds)
Term
 14.1. Explain the principle of coupled energy transfer
Definition
 Using a molecule of high energy and transfering it to another molecule (of lower energy) to make it reactive
Term
 14.2. Explain making glycogen with coupled energy transfer
Definition
 Glucose enters the cell and is activated by ATP so it can't leave the cell Glucose is now G-6-P This is an energy transfer G-6-P is activated by UTP to become UDP-Glucose This is an energy transfer UDP-Glucose adds G-1-P to Glycogen (and UDP pops off) This is another energy transfer
Term
 15.1. What is an "electron shuttle"?   15.2. Give 2 examples
Definition
 15.1. A molecule that transfers electrons from one molecule/reaction to another molecule/reaction   15.2. Electron Shuttles NADH- NAD+ can be reduced (gain a hydride (1 H+ and 2 electrons)) to NADH FADH2- FAD+ can be reduced (gain 1H+ and 1 electron and then gain another 1H+ and 1 electron) to FADH2
Term
 16. What do NADH and FADH2 electron shuttles do? (Where are they created and where do they go?)
Definition
 Electrons are transferred from molecules to NAD+ & FAD+ to form NADH & FADH2. These electrons come from glycolysis & the TCA Cycle NADH & FADH2 go to the ETC & transfer their electrons to proteins in the ETC Through a series of redox reactions, the ETC creates a H+ gradient The energy of the H+ gradient drives ATP Synthase to make ATP
Term