CBNS 120 MT 1 Review

1. Em deviates at low [K+]o primarily due to

• driving force for K+
• Na+/K+ ATPase
• Na+ conductance
• Ca2+ conductance

2. How do invertebrates typically increase conduction velocity?

• myelination
• glial cells
• increase axon radius
• saltatory conduction

3. Driving force is described as:

• Vm + Ex
• Vm - Ex
• (Vm)(Ex)
• Ex - Vm

4. In a voltage clamp experiment:

• membrane voltage is kept constant
• membrane voltage is manipulated
• membrane current is kept constant
• action potentials are recorded

5. Which of the following is true regarding a voltage-gated K+ channel?

• contains 4 voltage sensors
• contains 6 transmembrane segments per subunit
• blocked TEA
• blocked by TTX

6. The Goldman equation takes into account the effects of

• voltage-gated Ca2+ channels
• Na+/K+ ATPase
• leak K+ channels
• Cl- movement

7. To increase the conduction velocity in an unmyelinated axon, you can increase

• time constant
• internal resistance
• length constant
• axon radius

8. The nicotinic Acetylcholine receptor contains:

• a voltage sensor
• 2 acetylcholine binding sites
• 6 subunits
• an inactivation particle

9. Which of the following is true regarding NCX?

• sodium goes against its concentration gradient
• net positive charge flows out
• sodium enters the cell while calcium exits the cell
• requires ATP

10. if [Na+]o was reduced:

• ENa also reduces
• Action potential amplitude increases
• Action potential amplitude decreases