You've Just Isolated a New Bacterium in Pure Culture, and You

question 69

Multiple Choice

You've just isolated a new bacterium in pure culture, and you culture it on a general purpose medium where its cells have a rod-shape (bacillus) morphology. In addition to culturing it on solid media, you inoculate a slide to grow it as a bio?lm. When you use confocal microscopy to image the bio?lm, you observe that there are several cellular morphologies, ranging from coccus to coccobacillus to long bacillus. The best explanation for this observation is that _______.

• A) the bio?lm is no longer a pure culture of the microbe
• B) the bio?lm culture was not incubated under the appropriate conditions
• C) the microenvironments within a bio?lm promote structural variation
• D) the confocal microscope is out of adjustment

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Definitions:

Retinal Image

The image formed on the retina of the eye, where light-sensitive cells convert it into neural signals for the brain to interpret as visual information.

Linear Perspective

A technique in visual art and photography that creates the illusion of depth on a flat surface, indicating that objects appear smaller as they recede in space.

Parallel Lines

Lines in a plane that never meet, no matter how far they are extended.

Ambiguous Figure

A visual image that can be understood or interpreted in more than one distinct way.