Anatomy homework help
2401-20F EXAM 4
Name_____________________________
Microelectrodes are inserted into a neuronal cell, and the potential was recorded at points A and B. The potential is shown in Table 1. The electrodes at A and B are 30 mm apart. Based on the data presented here, answer the questions (1)~(4). 10 points total
Table 1. Membrane potential at points A and B.
Time (ms) | Vm (mV) at A | Vm (mV) at B |
0 | -70 | -70 |
0.4 | -52 | -70 |
0.8 | 37 | -70 |
1.2 | -15 | -70 |
1.6 | -75 | -55 |
2 | -80 | 38 |
2.4 | -75 | -18 |
2.8 | -70 | -70 |
3.2 | -70 | -82 |
3.6 | -70 | -75 |
4 | -70 | -70 |
- In the graph below, plot the data. Use two different colors or styles of lines for the data at points A and B. (4 points)
- Do the graphs resemble action potential? Why or why not? (1 point)
- Given that the distance between point A and point B is 30 mm, calculate conductance velocity (speed) of the neuron in m/s (4 points). Assume the same depolarization event was passing points A and B. Show the steps to get full marks.
- Based on your answer in (3) and Table 2, what kind of neuron is shown above? (1 point)
Table 2. Velocity of nerve conduction.
Neve fiber type | Conduction velocity |
Myelinated alpha | 70-120 m/s |
Myelinated delta | 12-30 m/s |
Unmyelinated | 0.2-2 m/s |