Online activity #1 (Unit III)

1. What is the electrode measuring?

In this experiment, we used a microelectrode. Electrodes record the activity of neurons in the leech.
2. Why use leeches in neurophysiology experiments?

Although leeches are basic, they give us a good idea of how more complex organisms work. Also, many people don’t have an emotional attachment to leeches, and don’t really mind if they are operated on. 3. What is the difference between a sensory and a motor neuron?

Sensory neurons are nerve cells within in the nervous system that are responsible for converting external stimuli from an organism’s environment. In humans, these are usually located in the spinal cord. Motor neurons are located in the central nervous system, and project their axons outside this system in order to control muscles.
4. Do you think a leech experiences pain? What is pain?

Pain is defined as an unpleasant sensation. I believe that although leeches are simple creatures, they can experience pain, just like most other organisms. I also think that they can experience pain because at the beginning of the experience, we had to put anesthesia in the leech. 5. What were the two most interesting things about doing this lab?

I thought that it was interesting when the dye went into the leech, and you could see everything internally and fluorescent. It was also interesting being able to use all the different tools in order to examine the leech.6. Anything you found confusing or didn't like about the lab?

I don’t like that I can’t even copy the pictures in the labs, but other than that the labs are fine.

Picture descriptions (because I can’t copy the pictures):

The ultraviolet image of the neuron with dye in it showing is has the shape of a sensory neuron. After the leech is cut open, and the dye is injected, and the UV switch is turned on, the outside shape is a green florescent diamond. There are two thin lines that come down from the top, and another line from the middle crossing the top lines. Off of the bottom lines are many more smaller lines, which are the axon and dendrites. In the right hand corner, you can see a bright circle, which is highlighting the neuron.

Now in the oscillope trace readings, I was able to identify a cell by using the probe. I identified that the “P cell” was the correct type in this experiment.