Paramecium bursaria in need of some sun!

[Charles Krebs]

Most of the Paramecium bursaria I have observed have been from "fresh" samples, or from samples that I have kept in good light. With these, the internal algae is extremely plentiful and bright green. This specimen came from an "old" container that was not kept near adequate light. Compared to others I have observed it looked rather anemic in the "greenery" department! But I was able to get a nice shot of the oral groove that also showed some interesting surface texture of the pellicle.

Olympus 100/1.40 S Plan Apo, Canon 350D. DIC with electronic flash.

[beetleman]

There is a lot of interesting detail in that photo Charles. The whole oral groove area and the cilia are fantastic

[bernhardinho]

Hi Charles,

very interesting image!!

Those individuals are referred to as aposymbiontic. Being deprived of light the algae don't deliver maltose anymore and the Paramecium takes up more and more food from the environment. thus increasing it's dividing rate and exceeding that of the zoochlorellae. It takes a couple of generations to create symbiont free individuals. This only happens in culture and never under natural circumstances, because evolution lead to a well balanced coordination of the dividing rates of the host and the symbiont, both taking advantage from each other.


Bernhard

[Ken Ramos]

Great image as usual there Charlie , looks as though it could use a bit more light or at least the algae could. Also an interesting bit of information there Bernhard.

[Charles Krebs]

Thanks guys!

Bernhard... appreciate the additional info! We can always count on you to add interesting details, and great web links too!