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Frog Heart Lab

Frog Heart Experiment
To examine the effects of pre-tension, temperature, and various drugs on the frog heart muscle,
specifically contraction strength and heart rate.
There are a number of external in influences that can affect cardiac output. Some of these are mediated
by the autonomic nervous system (ANS) and other responses are due to temperature changes and ionic
concentrations. Some of the chemicals used in the lab are; caffeine, epinephrine, and cadmium chloride.


Hey Chris,
Very very helpful and illustrative video, but may I suggest adding ("explicit material") to your title.  As many bio, chem, and science folk may really love this, I believe that younger wyzant users (and squeamish older ones) may be a bit disturbed. Keep up the great work!
Is this really necessary?  I'm not young or squeamish, but I know there are computer models for learning this.  Frogs, like bees are dying in droves.  No one is sure why, but given that they are, wouldn't it be more prudent to use a human cadaver heart or computer simulation instead of a frog?  
I respect your concern for the amphibian population, Kathryn. The frogs are probably dying due to some type of chemical runoff into their environment, caused by humans of course. This video was taken several years ago while I was in college. The experiment was one required to pass the course. As sad as it may be, frog hearts are more readily accessible than human hearts, thus the use of a frog in this lab.
Thanks for answering, Chris.  I hope someday, no animal will be killed for dissection purposes.  What I mean is human anatomy differs greatly from frog anatomy, so the very best way for humans to study human anatomy, physiology, pathology, etc. is to study humans. Computer modeling has already replaced some of what used to be done by animal stand-ins because many scientists and doctors saw the errors made from this paradigm. For example, rats are able to tolerate a higher concentration of nicotine than we can (their livers are larger, comparatively, than ours), so test results were coming back skewed. Infants who got into their parents' ashtrays were dying after said parents were being told by emergency personnel that their children hadn't ingested enough nicotine to harm them!  Thalidomide is another example.  They tested it on every animal they could think of, and when no contraindications appeared, they gave it to pregnant women.  We all know how that turned out!  Animal tests are just not reliable. When animals survive without complications, they start testing on humans anyway!  In early trials of promising childhood- leukemia drugs, a lot of kids died before the concoctions were refined by human testing, to be what they are now. That's what really happens.
Drifted a bit off topic and don't want to take up any more of your time.  Thank you for letting me know this video was made years ago. You, like many others, were stuck in that time warp. There are still institutions of higher learning that use poor benighted animals instead of modern methods, but they're steadily being replaced.  Frogs are bad enough, but think about man's best friend: trusting, loving dogs - tortured, dismembered, blinded, hobbled, and finally killed for "science" or veterinary school projects, or surgical practice or cosmetic "safety" testing (all in a database already, so especially repugnant). Such things make me feel horrible. There is a better way, but resistance to change is always the stumbling block.
All best, Kate