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Frogs Legs and electricity ?

  1. Sep 28, 2005 #1
    Does anyone have any advice about the best way to set up a demonstration of how muscle tissue can be stimulated by electricity?

    Specificly how frest does the tissue have to be?

    Is material you can buy at a good butcher shop likely to be fresh enough and how long will it last?

    From what I've read so far I get the impression that white meat is better than red and heart tissue is quite good for this demonstration but I really want to demonstrate a muscle contraction capable of doing some piece of physical work.

    I also get the impression that AC current is best but I'm not sure what voltage to use. I suppose it's an excuse to play with my variac.
  2. jcsd
  3. Sep 28, 2005 #2
    Unless this demonstration is for an advanced biology, pre-med, or nursing program, I am against this type of laboratory exercise that results in death of frogs in these times of well documented declines of amphibian populations worldwide. Have you ever decapitated or pithed a frog ? :yuck: -- but this will be required for this type of exercise because the muscle must be fresh.

    Here is my suggestion. Take a look at these internet sites that give alternative teaching aids:

    http://www.soveinc.com/ (play the sample video showing the demonstration you seek)

    http://www.eurca.org/res_desc.asp?EdID=392376 (This is called "SimMuscle")

    https://netfiles.uiuc.edu/ro/www/StudentsImprovingtheLivesofAnimals/dissection.alternatives.html [Broken] (see SimNerve software--is used by university professor to demonstrate frog muscle physiology).
    Last edited by a moderator: May 2, 2017
  4. Sep 28, 2005 #3


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    Electricity may trigger a muscular contraction but it does not mean that it is an electrical engine.
  5. Sep 29, 2005 #4
    Yes that's why I don't want to use frog. Is thier any reason to use frog other than historical ones?
  6. Sep 29, 2005 #5
    i realise that and understand it'll only do so much before it is exhausted.
  7. Sep 29, 2005 #6
    I've done this experiment with a frog's leg muscle. I'm not sure if butcher meet will show a significant contraction because the ion gradients required to make the action potential are being lost as the ions diffuse towards equilibrium. The more fresh the specimen the better the contraction. Also the muscle has to be prepared in a way so that it isn't significantly damage since that too will also have an effect on the contractions.
  8. Sep 29, 2005 #7
    Hi Marblemad.... Patty here.

    When we did this experiment in college, we used pithed frogs. In other words, the heart was still beating. The frog was brain dead -

    Pithing involves sticking a needle into the base of the brain. You can then dissect the frog, observe the beating heart, observe and measure muscle contraction, and so on.

    I don't have the stomach for this sort of experiment, but I respect that others may.

    As far as amphibian populations.... most labs get their frogs from breeders, so there should be minimal (if any) environmental impact.
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