© R. Neumeyer 1996
This image is "grabbed" off an Ektachrome 100 slide, using a Snappy video grabber. The original bright field photomicrograph was taken using a Zeiss Neofluar 40x, a Leitz Periplan 10x eyepiece and a Zeiss series IV achromatic-aplanatic condenser. The camera was a Canon T90, the specimen illuminated by the camera's dedicated flash, the TL300. The flash pulse was delivered concurrent with the normal halogen-tungsten light using a beam-splitter.
This image, and the image right, shows the habitat of a unique group of Chlorella, the Zoochlorella. These are the spherical, or ovoid green single-celled algae within the bodies of the protozoan, a member of the class Hypotrichea. The Hypotrichea can survive without the algae, and one assumes the same is true for the Chlorella. These symbiotic relationships range from commensalism (mutually beneficial) to parasitism (one benefits at the expense of the other).
In the example shown the relationship is probably commensal, as it would be in most cases, where the algae gains protection, and possibly some essential nutrients from the general protoplasmic soup inside the protozoan.
The benefit to the protozoa is less clear. However, it is possible that the Zoochlorella provides vitamins, proteins and of course starch, which may sustain the animal over the long haul in the absence of abundant external food sources. Of course, if worse comes to worse, then the protozoa likely digest and utilizes the entire algal biomass. Exactly how the initial relationship is established is not clear to me, maybe some readers have investigated this and would care to comment??
The Micscape and Microscopy UK Editors thank Ron Neumeyer for submitting this month's stunning Image of the Month.
The author, Ron Neumeyer can be contacted by Comments to the author sent via our contacts page quoting page url plus : ('rneumeyer','')">Email.
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