Chapter 5

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Chapter 5
2014-03-09 19:05:56

Cards for chapter 5
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  1. Potential Energy
    •which is energy stored up, ready to use, like a coiled spring, the capacity to do work. Also known as stored energy.
  2. Kinetic Energy
    •which is energy of motion, actually doing work.
  3. First Law of Thermodynamics
    •Energy is neither created nor destroyed, it just changes form. It’s about amount of energy in the universe. The total mount of energy in the Universe is constant.
  4. Second Law of Thermodynamics
    •states that disorder (entropy) increases.  Energy goes from useful forms to useless heat.
  5. Chemical Reaction
    The making and or breaking of chemical bonds.
  6. Reactants of Substrates
    The original molecules before the chemical reaction occurs
  7. Products
    The molecules that are formed as a result of the chemical reaction.
  8. Endergonic Reaction
    These are chemical reactions in which products contain more potential energy than the reactants. They require energy to proceed and are not spontaneous.
  9. Exergonic Reaction
    These are chemical reactions that release energy. The products contain less energy than the reactants. These reactions are spontaneous.
  10. Activation Energy
    The energy required to start a reaction
  11. Catalysis
    The process of lowering the activation of the chemical reaction. Note, catalysis cannot make an endergonic reaction occur spontaneously, you cannot avoid the need of energy. It can make both chemical reactions go faster.
  12. Enzymes
    • Proteins that cause specific chemical reactions to occur.
    • Enzymes act as catalysts, they help the reaction occur, but they aren't used up in the reaction.
  13. How do Enzymes work?
    • They first bind to a specific molecule. The
    • substrate binds to the enzyme’s active site and lowering the activation energy for a reaction.  The reaction occurs  thousands or millions of times faster than without the enzyme.  The little bit of activation energy needed is supplied by the collision of the molecules involved.
  14. Active Site
    Special region of an enzyme that holds substrates together and causes them to react. The active site promotes the reaction by orienting the substrates properly, straining their bods so they break more easily, and by providing acidic or basic amino acids to help the reaction along. The perfect fit of the enzyme is with the reactant is called induced fit.
  15. Binding Site
    Where the enzyme binds. So Binding site is the spot on the reactant that binds to the enzyme.
  16. Biochemical Pathways
    Series of chemical reactions involving different kinds of enzymes. Every organism contains thousands of different types of enzymes that work together to perform variety of chemical reactions. The product of one becomes the substrate for the next reaction.
  17. Factors affecting enzyme activity
    1. Shape 2. Temperature and Ph 3. Salt level
  18. Enzyme Inhibition
    When a molecule called a repressor binds to the enzyme and alters the shape of the active site so that it cannot bind to the substrate.
  19. Enzyme Activation
    Some enzymes need to be activated. A molecule called an activator binds to the enzyme and changes the shape of the active site so that it is able to bind the substrates. Enzymes controlled in this way are allosteric enzymes.
  20. Competitive Inhibition
    A repressor molecule can bind to the active site of the enzyme, blocking it.
  21. Non-competitive Inhibition
    When the repressor binds to a different site on the enzyme, so that the enzyme cannot bind its substrate.
  22. ATP
    In living cells, energy for immediate use is stored as molecules of ATP, Adenosine triphosphate. Composed of a sugar, adenine (Which is one of the nitrogenous bases in DNA and RNA) and three phospates that contain high energy bonds.
  23. Generating ATP from Food
    Making ATP requires energy, which comes form the potential energy stored in food molecules. More specifically, electrons from glucose or other food molecules are passed through a series of steps, biochemical pathway, releasing part of their energy in each step, and ultimately ending up attached to oxygen. The energy from the electrons going down the energy hill is used to create ATP from ADP and phosphate.