Introduction to Metabolism

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					Introduction to Metabolism

         Section 1.3
ENERGY
 Living organisms must continually capture, store, and use
  energy in order to function
 ENERGY: __________________________.
 Organisms do all of their work at the ____________ level.
 Needed for catabolic reactions:
   Amylose  ______________  _________ + _______
 Needed for anabolic reactions:
   Phosphate + sugar + ______________  nucleotide  ___
 METABOLISM: sum of all __________________ and
  ___________________ reactions in a cell or organism.
TYPES OF ENERGY
 All forms of energy can be classified as KINETIC or POTENTIAL
  energy.
 Kinetic energy: energy possessed by moving objects.
     Examples?
     Thermal energy: random motion of particles
     Mechanical energy: coordinated motion of particles
     Electromagnetic energy: motion of light
     Electrical energy: motion of charged particles.
 Potential energy: stored energy
   An object possesses potential energy because of its position within an
    attractive or repulsive force field.
   Gravitational potential energy: attraction between two objects
   Chemical potential energy: attraction of electrons to protons in a
    chemical bond.
   THE DIVER
 A diver on a diving board possesses _____________ energy
  because of the force of _____________ between him/her and
  the Earth, and the distance between the two.
 The diver must have done __________ to gain this
  ________________ energy.
 When the diver dives, the ________________ energy is
  converted to _________________ energy.
The First Law of Thermodynamics
 Total amount of energy in the Universe is constant
 Energy cannot be created or destroyed, only ___________
  from one form into another.
Usable Energy
 In organisms, energy is usually stored before being used.
 Ex// plants capture ___________ energy and convert it to
  chemical potential energy in _______________ and may
  be stored in that form before being used. Through the
  reactions of cellular respiration, the chemical energy in
  ____________ is passed on to ______.
 ATP: the primary energy-transferring compound.
 ATP may be used to activate protein carriers which transport
  ions through a cell membrane ______________ the
  concentration gradient, building up ______________
  potential energy.
Bond Energy
 Molecules possess stability because of the chemical bonds between
  their atoms.
   The atoms achieve a greater stability by attaining a stable
    ___________________ electron configuration.
 Bond Energy: measure of the stability of a covalent bond.
ATOMS NOT IN A BOND CONTAIN MORE ENERGY THAN
  ATOMS IN A BOND.
   Equal to the minimum amount of energy needed to break the bond
    between two atoms.
   Equal to the amount of energy released when a bond is formed.
ENERGY IS __________________ WHEN REACTANT BONDS
  BREAK AND ENERGY IS __________________ WHEN
  PRODUCT BONDS FORM.
POTENTIAL ENERGY DIAGRAMS
 Shows the changes in potential energy during a chemical reaction.
 ACTIVATION ENERGY: amount of energy needed to break the bonds
  between reactants.
 TRANSITION STATE: temporary condition in which the bonds within
  the reactants are breaking and bonds between products are forming.
 ENTHALPY OF REACTION: ∆H: overall change in energy that occurs
  in a chemical reaction (the ‘system’).
 Deals with the NET ENERGY input or output.
   If bonds in products more stable than those in reactants: net energy
    ______________. This type of reaction is called an
    __________________________ reaction. The system ________ energy,
    meaning that ∆H is __________________.
   If bonds in products less stable than those in reactange: net energy
    ______________. This type of reaction is called an
    __________________________ reaction. The system ________ energy,
    meaning that ∆H is __________________
ENTROPY
 Measure of the disorder in energy or in a collection of objects.
   Increases when disorder increases.
 In chemical reactions, entropy increases when:
   Solid  ________  _______
   Fewer moles of reactant molecules form greater number of moles of
     product molecules:


   Complex molecules become simpler molecules:
    ______________________________________________.
   Diffusion: solutes move from an area of _____ concentration to an
    area of ______ concentration.
Gibbs Free Energy
 energy that can do USEFUL work.
 There is a relationship between the energy change, entropy
  change, and temperature of a reaction.
   Predicts if a reaction will proceed spontaneously or not.
DIFFERENCE BETWEEN ENERGY AND FREE ENERGY?
Aquarium example:




PURPOSE: to turn the blades of the fan.
Both aquariums start with same amount of total energy.
Aquarium 1: water moves from more ordered state (low entropy, higher free energy)
  to less ordered state (high entropy, lower free energy)  release of free energy.
Aquarium 2: blade does not move: contains ENERGY, but does not contain FREE
  ENERGY.
 Thermal energy: molecules are moving, but are not doing any ‘useful’ work.
SPONTANEOUS REACTIONS
 If decrease in Gibbs free energy  spontaneous.
   Gibbs free energy: ∆G
   Change in Gibbs free energy: ∆G = Gfinal – Ginitial
   If ∆G is negative, ___________________ reaction.
   If ∆G is positive, ___________________ reaction.
   A spontaneous reaction is ________________________ in
    the reverse reaction.
     Aquarium example: work must be done to reestablish the conditions of
      aquarium 1 (more order, more free energy)
       From another reaction!!!
SECOND LAW OF THERMODYNAMICS
 The entropy of the universe increases with any change that
  occurs.
   Example: Geevithan eats a potato chip:
     Getting chip to mouth: increase in gravitational potential energy, decrease
      in entropy (more ordered)  increase in Gibbs: needs energy to do
      work.
     Energy for the work is derived from converting ordered nutrients
      (glucose) into more disordered carbon dioxide, water molecules, and
      other wastes: _________________ reactions.
     In the end, amount of disorder created in the ‘reaction’ is greater than
      order  net amount of disorder in universe.
DEFINITIONS:
 EXERGONIC: a chemical reaction in which the energy of
  the products is less than the energy of the reactants; chemists
  call this an ___________________ reaction.
   Is spontaneous: ∆G is _____________________.
 ENDERGONIC: a chemical reaction in which the energy of
  the products is more than the energy of the reactants;
  chemists call this an ________________ reaction.
   Is nonspontaneous: ∆G is ________________________.
SPONTANEOUS CHANGE, FREE
ENERGY, AND WORK
Yeah... So?




COOOOOOOOOOOOOOOOOOOOOOL.
Metabolic Reactions
 Reactions of metabolism are ENZYME CATALIZED and are
 all reversible.
   When a reversible reaction reaches equilibrium, its ∆G is zero.
   No free energy = ________________ cell.
ATP  OUR HERO!!!!
 ATP: primary source of free energy in living cells.
 Made of: _________________, _________________,
  and ___________________.
 When a cell requires free energy to drive an
  ______________________ reaction, an enzyme called
  ATPase catalyzes the ______________ of the terminal
  _______________ of an ATP molecule, resulting in
  _____________ and _____. 31 kj/mol of free energy is
  released.
The free energy released during the
hydrolysis of ATP is not heat... Why?
 A single working muscle cell uses about
  _____________________________ ATP molecules per
  minute.
 An active body consumes _________________ in ATP per
  day.
Phosphorylation
 Phosphate group attached to an organic molecule (like ADP
  or a protein pump)
HOMEWORK:
 Read section on Redox Reactions (page 66-67)
 PPs pg. 68 #1-10.

				
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posted:10/14/2011
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