LEECH NEUROPHYSIOLOGY LAB

LEECH NEUROPHYSIOLOGY LAB

·     What is the electrode measuring?

 Electrodes are what you use to record the activity of the neurons. The generic term "electrode" is defined as a conductor that is used to establish electrical contact with a nonmetallic substance. With the use of florescent dye the neurons can be seen using a dissection microscope.

·     Why use leeches in neurophysiology experiments?

Leeches have been useful in many experiments in the function of the nervous system. Leeches have a simple nervous system so it’s easier to understand. Many first discoveries were found in leeches.  Leeches has 21 segmental ganglia, each containing 175 pairs of neurons. The reasonably small number and the large size of the neurons have made leeches favorite subjects of neurobiologists.

 

·     What is the difference between a sensory and a motor neuron?

Sensory neurons take nerve impulses or messages from a sensory receptor to the CNS.  The Motor neuron takes nerve impulse away from the CNS to effectors. The difference between both is that they both take nerve impulses to different locations. The sensory sends messages to the CNS and motor neuron takes it away from the CNS.

·     Do you think a leech experiences pain?  What is pain?

Leeches have a nervous system so I would believe that they feel some sort of pain during experiences. During this experience, the leech was dipped in 20% ethanol solution. It can be use for smaller creature as an anesthesia like a leech that breathes through their skin.  Pain is an unlikable sensation.  When there is harm done to our bodies to any creature’s bodies it can cause a discomfort or agony.

·     What were the two most interesting things about doing this lab?

To dissects a leech online. After doing this experiment I never knew anything about leeches and how useful they have been in discovering many functions with the nervous system. To learn more about neurons and how it looked after I put the florescent dye in and then the light and how each neuron look different from one another. The pictures of the neurons were specific because I felt like I was really doing the experiment even if it was on a computer.

·     Anything you found confusing or didn't like about the lab?

It took me awhile to figure out how to actually get a neuron at first but other than that it was a great lab!

 

an Image of the leech with the oscillope trace.

 

Cell Types that are inside a Leech's Nervous System

A screen shot of a R Cell that was found in the leech's nervous system.