Answer multiple choice problems on neurotransmitters

1.  describe at the peak of the action potential the magnitude of the driving force on K+ is

1) less than that of Na+

2) greater than that of Na+

3) the same as that of Na+

4) none of the above

2. describe what is the mechanism of action of nicotine?

1) It transforms into acetylcholine.

2) It causes more acetylcholine to be released into the synapse.

3) It is an acetylcholinesterase antagonist.

4) It directly binds to and opens an ion channel.

5) None of the statements above is correct.

3.  describe an enzyme that directly converts a precursor molecule into an active neurotransmitter is

1) Acetylcholinesterase

2) Tyrosine hydroxylase

3) Tryptophan hydroxylase

4) Glutamic acid decarboxylase

5) All of the above.

4. describe you are an axon in the arm of a new-born baby waiting to be myelinated. Who do you wait for?

1) schwann cells

2) astrocytes

3) oligodendrocytes

4) microglia

5. describe if the potential of a membrane containing Cl- channels was held at +80 mV the net flow of Cl- ions would be

1) Inward with its concentration gradient and against the electrical gradient.

2) Inward against its concentration gradient and with the electrical gradient.

3) Outward with its concentration gradient and against the electrical gradient.

4) Outward against its concentration gradient and with the electrical gradient.

5) None of the above.

6. describe a mutant form of the voltage-gated Na+ channel is isolated that allows both Na+ and K+ ions to pass. This mutation is most probable to affect amino acids located in the

1) First transmembrane domain (S1).

2) Fourth transmembrane domain (S4).

3) Sixth transmembrane domain (S6)

4) P region

5) The delayed rectifying K+ channel

7. Define adding a Barium solution to a typical neuron at rest would cause it's membrane potential to

1) depolarize.

2) hyperpolarize.

3) remain unchanged.

8. describe there are few voltage sensitive potassium channels located at nodes of Ranvier

1) true

2) false

9. Imagine you are an aspiring neuron however don't have any ion channels on your membrane. Your inside as well as outside concentrations of ions are physiologically normal and you only have enough resources to produce one type of ion channel. What kind of ion channel should you produce if you want your resting membrane potential to be most similar to that of a typical neuron

1) Na+ channel.

2) K+ channel.

3) Cl- channel.

4) Ca++ channel.

5) None of the above.

10. The dendrite with the longest length constant would be

1) Narrow and leaky

2) Wide and leaky

3) Narrow and not leaky

4) Wide and not leaky