Many chemicals are kept from passing from the circulatory system ...

[kwoodring]

Many chemicals are kept from passing from the circulatory system of the CNS into CNS neurons by
 
  A) reflexology.
  B) the blood-brain barrier.
  C) tolerance.
  D) the cerebrospinal fluid.
  E) withdrawal.

Question 2

The main disadvantage of the oral route of drug administration is
 
  A) indigestion.
  B) the binding of drugs to the wall of the stomach.
  C) its unpredictability.
  D) nausea.
  E) that it promotes drug interactions.

[covalentbond]

Answer to Question 1

Answer: B

Answer to Question 2

Answer: C