Online Lab: Leech Neurons

Leech Neurophysiology Lab:

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QUESTIONS ABOUT LEECH NEUROPHYSIOLOGY LAB:(Answer these questions to get full exemplary lab credit (A-level, 18-20 points)

1. What is the electrode measuring?

A-It is measuring the voltage of individual neurons.

2. Why use leeches in neurophysiology experiments?

Because it has been found that simple systems are easy to understand.
Simple nervous systems follow many of the same rules as more complex ones like
humans, so results that occur in the more simple systems may be directly relevant in
trying to understand the more complex human brain.
They are favored because of small number and large size of neurons.

3. What is the difference between a sensory and a motor neuron?

A sensory neuron is a nerve cell that transmits impulses to the central nervous system (spinal cord or brain). It is information such as taste, touch, hot, cold, sound, sight or pain. A motor neuron is a nerve cell that transmits direction to muscles and organs from the central nervous system to perform some function.

4. Do you think a leech experiences pain? What is pain?

A- No- First because it was anesthesized on the simulator prior to dissection. I also don’t think a leech experiences hardly any pain because they don’t have the “input region” of nerves to receive pain information signals plus they do not have brains that receive signals like humans do. They have no dendrites or synapses to relay pain messages like humans and many higher evolved species.

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

A- I thought it was fun doing the mock dissection and also being able to check out the different electrical currents with the different tools.

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

A- The only thing difficult was realizing I needed to play with it long enough to get familiar with the diiferent things it could do and what my lab requirements were for the project.