The lab report also details the results of a negative stain performed on the bacteria in the urine sample, in which the background of the sample is stained, rather than the cells themselves. The report indicates that the cells have a clear halo around them, indicating the presence of a(n) ________. You explain to Petrus that this structure helps bacteria avoid ________, part of the immune response.
A) endospore; phagocytosis
B) flagellum; antibodies
C) LPS; antibodies
D) capsule; pinocytosis
E) capsule; phagocytosis

Question

Quizplus · Accepted Answer

The clear halo around the cells indicates the presence of a capsule, which helps bacteria avoid phagocytosis, a process in which immune cells engulf and destroy foreign particles. Answer choice A is incorrect because endospores are resistant structures formed by some bacteria in response to adverse conditions, and they are not present in all bacteria. Flagella (B) are structures used for motility, and LPS (C) are components of the cell wall that can trigger an immune response. Choice D is incorrect because pinocytosis is a process in which cells take up fluid rather than large particles like bacteria.

The Lab Report Also Details the Results of a Negative