Didnium
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Transcript of Didnium
![Page 1: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/1.jpg)
Didnium
Eaters of the Dead…
Dead paramecium that is!
![Page 2: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/2.jpg)
I began experimenting with a pure culture of Paramecium which looked like this, --virtually nothing but the torpedo-shaped paramecia.
![Page 3: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/3.jpg)
Now, after only one day, it looks like this -- virtually all the organisms to be found are a more spherical ciliate with two bands of cilia.
![Page 4: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/4.jpg)
The organism that has wiped out all the paramecia is Didinium, a predator that feeds on only one
kind of prey -- Paramecium. Now there are a lot of Didinium -- and they are starting to get hungry.
This presents an excellent opportunity to study and record
their feeding behavior.
![Page 5: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/5.jpg)
The Capture:
I add some paramecia back to the culture dish. Didinium speeds around in a random way, nose first. When it hits a Paramecium, poison darts fire automatically. Didinium then begins opening its nose, which becomes its mouth, and it begins to swallow the much larger cell.
![Page 6: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/6.jpg)
Notice the cilia all around the didnium and the paramecium. The nose hairs paralyze the paramecium.
![Page 7: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/7.jpg)
The Pig Out
*I was able to observe an interesting aspect of Didinium’s swallowing technique.
*With part of the Paramecium engulfed, Didinium expands, thereby sucking cytoplasm from the part still extending from its mouth.
*If the prey was hit in the middle, Didinium expands its mouth and folds the paramecium in order to cram it all in.
![Page 8: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/8.jpg)
The Didnium is over the top of the paramecium.
![Page 9: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/9.jpg)
Engulfment by folding prey.
![Page 10: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/10.jpg)
Sometimes they must share.
![Page 11: Didnium](https://reader036.fdocuments.us/reader036/viewer/2022071712/56812c44550346895d90c9b2/html5/thumbnails/11.jpg)
Parts to look for in Didnium:
*Cell Membrane
*Nucleus
*2 rows of cilia
*Oral Cavity
*Describe locomotion