Biology 172 Lecture 4

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  2. The _____ of the protein is critical for its function
    • Shape.
    • Because of its specific shape (conformation) the groove region recognizes and binds target molecules on the bacterial walls
  3. Lysozyme
    an enzyme in saliva that attacks bacteria
  4. Why does a protein always assume a particular conformation (native state) and not others?
    Structure both determines and limits function
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  7. Proteins fold into a conformation of ____ ______
    lowest energy
  8. What factors effect cell environment?
    • Temperature
    • Salts (Ions)
    • pH
  9. A single amino acid substitution in a protein causes ______ ________
    • sickle-cell disease
    • Defects in protein folding can have profound consequences
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    Denaturation is bad. Sometimes can't renature protein
  12. _________ help protein folding in the cell .
    Chaperones
  13. Chaperone Protein
    has quaternary structure cap protein must be part of chaperone complex to be fully active structure
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    Prions cause fatal diseases when misfolded: mad cow ....
  15. Energy
    the capacity to do work
  16. Potential energy
    energy 'stored' in an object
  17. Kinetic energy
    energy of motion, includes motion at the molecular scale (heat)
  18. Types of work
    • mechanical
    • chemical
    • kinetic (heat) energy
  19. Energy is described by ...
    Law of Thermodynamic Motion
  20. Change in free energy determines _________ ___________
    reaction characteristics.
  21. Energy-releasing reactions are ________
    Energy-releasing reactions are ________
    • exergonic
    • exothermic
  22. Energy-consuming reactions are ________
    Energy-consuming reactions are ________
    • endergonic
    • endothermic
  23. ΔG
    change in free energy. ΔG < 0 in a spontaneous reaction; free energy decreases (because some has been used up)
  24. ΔH
    • Difference in potential energy between the products and the reactions
    • (-) when heat is released
    • (+) when heat is absorbed
  25. ΔS
    • change in entropy = measure of disorder; increases in universe as a whole
    • (-) decreases in disorder
    • (+) increase in disorder
  26. Exergonic
    reactants have more energy than products; spontaneous; energy is released; ΔG < 0
  27. Endergonic
    reactants have less energy than products; non-spontaneous; energy is required (consumed); ΔG > 0
  28. Coupled reactions
    Overall ΔG is negative; together, reactions are spontaneous
  29. Activation Energy
    energy required for reactants to reach the transition state (unstable intermediate) ..... can be overcome by heat or a catalyst
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    How do the catalysts work?
    Catalysts work by binding to reactants (weak bonds) and lowering the Ea = energy needed to break / form covalent bonds
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Author
clintave
ID
130590
Card Set
Biology 172 Lecture 4
Description
Biology 172 Lecture 4 Exam Review
Updated