YES! We finally made it to the dissecting module! Unfortunately, I lost my brain and forgot my camera. My teaching partner had her iphone and was able to take photos and email them to me. I am so grateful, because I know all my 2.563 readers want to see the innards of worms. Thank you, Lynn!
In the 1.5 hours of class time, we had enough time to take a short quiz, dissect the worm, and clean up.
Everyone did a fine job with their specimens. Two of the six specimens were in great shape, three were ok, and one was dried and flat.
At the beginning of this experiment, each student had to cut open the bag and remove the worm. Only one girl had a problem with that, but once it was out she was fine with it.
First thing to find was the clitellum. Here I am, using my artistic side, drawing the worm and what the clitellum looks like. It’s been a long time since I have actually drawn anything. Ok, you can stop laughing now.
This was the point when I told the class they had to wait to put on the gloves. They needed bare hands to look at the segments in the clitellum and feel for the setae. You should have heard the squeals, “WHAT?” “ARE YOU SERIOUS?” Yes, I am! 😀 It was really cool to feel them.
Look at this beautiful class! Everyone is busy examining their worm. Be still my heart!
The hardest part of dissecting a worm, is making the first cut. It is very important to be careful not to cut too deep and cut through any organs. Some of the class was able to do this and some were not. It was interesting for the students to see dirt in the intestines. Got a lot of ewwww…. from it. lol
The second hardest part was pinning the sides down, but everyone did a great job with it. Once everything was open, we worked our way down from the anterior to the posterior.
As you can see in the above photo, this worm had its intestines cut. We were able to identify all the parts, including the aortic arches and the nephridia (kind of like kidneys). The nephridia were found in only one of the worms and a magnifying glass was needed to see them.
Everything was cleaned with alcohol, throughly dried, and put away. Next up will be the crayfish. 😀
If you would like to see some interesting videos of the aortic arches go to The Yucky Site and click on the link that says Heart Beat Video. There is also one for birthing. Very interesting.
I hope you enjoyed this section. 🙂