Bio 117 Practice test #2

  1. True or false (if false, provide the correct information):
    • Action potentials are the result of hyperpolerization.
    • FALSE. They are the result of depolarization.
  2. True or false (if false, provide the correct information):

    Graded potentials can only occur through depolarization.
    FALSE. They can occur through either depolarization or hyperpolerization.
  3. Does depolarization make the membrane potential more or less negative?
    Depolarization makes the membrane potential less negative.
  4. Name the two enlargements of the spinal cord.
    The cervical and the lumbosacral enlargements.
  5. The nerves derived from the lumbosacral enlargement target which area of the body?
    The lower limbs.
  6. True or false (if false, correct the statement to make it true):

    Afferent cell bodies are located in the anterior and lateral grey horns.
    FALSE. They are located in the posterior grey horn.
  7. Where in the spinal cord are somatic efferent axons located?
    in the anterior white columns.
  8. What is the difference between a mixed nerve and a nerve that is not mixed? Give one example of each.
    • Mixed nerves carry efferent and afferent impulses (or you can say that they are made up of fibers that conduct efferent and afferent impulses). Non-mixed nerves carry only a single impulse type.
    • All peripheral nerves derived from spinal nerves are mixed nerves. All spinal nerves are mixed nerves, too. The spinal roots are not mixed nerves.
  9. Name the nerve that exits the spinal column immediately superior to L5 vertebra.
    L4 spinal nerve
  10. Name the nerve that exits the spinal column immediately superior to T1 vertebra.
    C8 spinal nerve
  11. Name the nerve that exits the spinal column immediately inferior to C1 vertebra.
    C2 spinal nerve
  12. Why are there 43 pairs of peripheral nerves but only 31 pairs of spinal nerves?
    • There are more peripheral nerves compared with spinal nerves b/c of somatic nerve plexuses. Nerve plexuses are networks of anterior rami of spinal nerves in which the anterior rami converge and diverge and ultimately form more peripheral nerves than the spinal nerves that form them.
    • For example, the brachial plexus is made up of five spinal levels (C5, C6, C7, C8 and T1), but there are 17 nerves made up of those five spinal levels.

    Similarly, there are five spinal levels in the lumbar plexus, but nine peripheral nerves. And there are six spinal levels in the sacral plexus, but 8 peripheral nerves.
  13. Which rami contribute to the formation of somatic nerve plexuses?
    Ventral/anterior rami
  14. Provide the name and spinal levels for each of the somatic nerve plexuses:
    • Cervical: C1-C4
    • Brachial: C5-T1
    • Lumbar: T12-L4
    • Sacral: L4-S4
  15. Which plexus are the lumbosacral trunks a part of?
    The sacral plexus
  16. Trace the path of the radial nerve through the brachial plexus.
    C5 and C6 / superior trunk / posterior division / posterior cord / radial nerve

    C7 / middle trunk / posterior division / posterior cord / radial nerve

    C8 and T1 / inferior trunk / posterior division / radial nerve

    All three of the posterior divisions converge to form the posterior cord, which continues as the radial nerve
  17. Which spinal levels contribute to the suprascapular nerve?
    C5 and C6
  18. Which spinal levels contribute to the long thoracic nerve?
    C5, C6, and C7
  19. Which spinal levels contribute to the medial cutaneous nerve of the arm?
    C8 and T1
  20. Which divisions form the lateral cord of the brachial plexus?
    The anterior divisions of the superior and middle trunks
  21. What are the spinal levels of the tibial division of the sciatic nerve?
    L4, L5, S1, S2, and S3
  22. True or false (if false, provide the correct information):

    Dorsal rami never contribute to the formation of somatic nerve plexuses
    TRUE
Author
ChathamBio502
ID
327618
Card Set
Bio 117 Practice test #2
Description
Cards for lectures 4&5
Updated