Using phase contrast microscopy on a wet mount of live cells, you observe motile bacilli moving rapidly and randomly through the field of view, changing directions after a brief tumble and taking off in a different direction. These cells are exhibiting ________ motility.
A) twitching
B) swimming
C) gliding
D) twitching or gliding

Question

Quizplus · Accepted Answer

The rapid and random movement of the motile bacilli followed by tumbling and changing direction is characteristic of swimming motility. Twitching and gliding motility involve different mechanisms of movement and are not consistent with the observed behavior.

Using Phase Contrast Microscopy on a Wet Mount of Live