BIOL 404-Exam 4-Muscle 10

  1. What is the action of Curare?
    • Competitively binds to Nicotinic receptors without opening their ion channels
    • Cannot be destroyed by Acetylcholine esterase
  2. What were the three non-depolarizing neuromuscular junction blocking drugs discussed in class?
    • Curare
    • Rocuronium
    • Vecuronium
  3. What are Curare, Vecuronium and Rocuronium?
    Non-depolarizing neuromuscular junction blockers
  4. What is the advantage of Vecuroniuma nd Rocuronium?
    Longer acting than Curare
  5. What muscle related drug can cause death by asphyxiation?
    Curare, as it can inhibit muscles required for breathing
  6. Other than non-depolarizing nicotinic competitive inhibitors, what alternate mechanisms are there for blocking neuromuscular transmission?
    inhibition of acetylcholineesterase
  7. What are examples of toxins that inhibit acetylcholinesterase?
    • Organo-phosphates
    • Found in nerve gas and fertilizers
  8. What is Succinylcholine?
    • Depolarizing/Desensitizing acetylcholine receptors Antagonist
    • Works similarly to acetylcolinesterase inhibitors
  9. Succinylcholine works similarly to what other drugs?
    Acetylcholinesterase inhibitors
  10. What is the action of Succinylcholine?
    Depolarizing/Desensitizing acetylcholine receptors Antagonist
  11. What is the generally potency of Botulism toxin?
    • One of the most potent toxins
    • Need very little to produce and effect
  12. What bacteria produces Botulism?
    Clostridium Botulinum
  13. What is Botulism toxin?
    An enzyme that breaks down the SNARE complex rquired for fusion of ACh vesicles with axon terminal
  14. What is the name for the substance that breaks down SNARE complexes, required for ACh binding to the axon terminal?
    Botulsim toxin
  15. What are common uses for Botulism toxin?
    • Overactive extraocular muscles
    • Excessive sweat gland activity
    • Treatment for migraines
    • Wrinkles
  16. Describe the structure of smooth muscle:
    • 1-2 um wide
    • 50-400 um long
    • Spindle shaped
  17. How does the size of smooth muscle compare to the size of skeletal muscle?
    Much smaller
  18. What are the dimensions of skeletal muscle?
    10-100 um wide and can be tens of centimeters long
  19. How many nuclei do smooth muscle cells contain?
  20. When do smooth muscle cells cease to divide?
    Never, can continually divide throughout a lifetime
  21. What filament component is not found in Smooth Muscle?
  22. What type of cells would you not expect to find Troponin?
    Smooth muscle cells
  23. What filament components would you expect to find in smooth muscle?
    • Actin
    • myosin
    • Tropomyosin
  24. What are think filaments in smooth muscle cells anchored to?
    • Image Upload 1
    • Plasma membrane or Dense bodies
  25. Describe the banding pattern of smooth muscle cells?
    No banding pattern due to lack of sarcomeres and myofibrils
  26. What type of muscle cell does not have myofibrils, sarcomeres or a banding pattern?
    Smooth muscle cells
  27. What is the mechanism for smooth muscle contraction?
    Sliding filament mechanism
  28. Where are smooth muscles found?
    Surrounding hollow organs that undergo changes in volume
Card Set
BIOL 404-Exam 4-Muscle 10
BIOL 404-Exam 4-Muscle 10