Frog Guts

As the title indicates this post is all about frog guts.  Don’t complain to me if you don’t like what you see.  You knew what was coming. 🙂

This is my last gut post for this year.  So enjoy it!

Module 13, experiment 13.2 is the Frog Dissection.  In this experiment the students are suppose to find their own protocol. Protocol is the instructions on dissecting whatever you are dissecting.  In this case it is the frog.  For the second year, this has been a disaster.

Most of my students either lost it, couldn’t find anything on the internet, dog ate it, or flushed it down the toilet.  So next year, I am writing up their protocols. I’m more interested in them learning about the frog, than finding their own protocol.  I walked them through it this year and we ran out of time.

The specimens were a mess.  I will not be ordering from this company again. But we did work with what we had.

First we take a look at the outside of the frog. Note, size, color, shape, guess the gender, etc.

The size of the tympanum membrane and the thumbs on the front legs is a good way to determine the sex of the frog.  Of course this is not always accurate.  If the tympanum membrane and/or the thumb are large, it is a male.  According to my students we had all males and one female.

They were wrong.  After making our first incisions, we found eggs.  If I am not mistaken, correct me if I am wrong, only females can have eggs.  A whole mess of eggs.  Nasty eggs.  Every.where.eggs!  But cool looking.

The eggs needed to be removed in order to look at the organs.  That was a fun job and I’m glad I didn’t have to do it. LOL

Here is what it should look like without eggs.  This one had no eggs, but some had eggs hidden under the organs.

After looking at what we could, some of the students started removing the liver, intestines and other things to see what was underneath.

One of the frogs had an impressive amount of fat bodies.  Fat bodies are used to store food/nutrients for hibernations or when there is a lack of food.   If you look just below the intestines, you’ll see some eggs.  You have my permission to print and frame this for your kitchen.  😀

Speaking of food, the stomach was opened up to see what was the last meal.  I really didn’t think we would find anything but…

this was found.  Do you know what it is?

I wish we had more time than 1.5 hours to dissect an specimen.  There isn’t enough time to dissect, take notes, sketch, etc.

I will be doing some things different next year. 🙂

Not enough frog guts for you?  Then read about last year’s Frog dissection 2010.

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11 responses to “Frog Guts

  1. haha, should I have dd come see what’s on the screen?
    I don’t have a Post-it Note large enough, lol. 😉

    What exactly was wrong w/ the specimens?
    When you find a good company you like, let me know. I plan to have my twins do the dissections when the time comes.
    By the time you get finished trying things differently each year, I should be ready, haha! 😆

  2. Thank you so much for blogging about your class and dissections & experiments. Our co-op is about a month behind yours (and everyone else’s!) because I was heading it up and needed to go take care of my mom after an emergency heart surgery. The benefit to that is that I get to learn SOOO much from your blog before I have to do these things with our own co-op!! As a first-timer in the biology co-op world, I am thankful that you are here to hold my hand! 🙂
    I notice the use of styrofoam plates to hold the specimens – do you find this easier/better than the ‘dissecting trays’? An equally good substitution for a fraction of the price? Or just a fill-in when students forget theirs?
    I, too, will be very interested in hearing about specimens from you.
    Also, what do you think is a good amount of time to do a dissection? I have 2 hrs, but could go longer, especially if I can notify parents in advance.
    Thanks so much!!

  3. Hey Applie – Great post! We were going to do the frog dissection last time we met (with the perch) and ran out of time and we have two hours. I may still have them do it next time, even though we’re moving ahead to Module 14….Definitely need better specimen too. Our perch was really dried out and difficult to work with.

  4. So what was it that was in the frog’s stomach?? Could you identify it?

  5. Your specimens looked better than ours!

  6. I feel bad for the poor froggies! And the poor eggs! They made me sad.

    But! I am happy this is the last dissection post. I hope that’s true and not some sort of trick to lure the unsuspecting.

  7. The first photo is funny. Good thinking to use the plates.

    I wonder things about the frog when I see them cut open, but I’ll keep them to myself.

    This is an informative article as usual. =) Thanks Michelle

  8. We are going to be dissecting again next year. Dissecting is my favorite part of Biology, but our specimens were not that great either. I am looking forward to your next post about them.

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