A bacterium has the following characteristics:
∙ It adheres to the human intestinal lining using a feature that protects it from phagocytes, bacteriophages, and dehydration
∙ It can survive being boiled
∙ It contains no plasmids and relatively little peptidoglycan
Which of the following statements best describe the cell wall of this bacterium?
A) Its innermost layer is composed of a phospholipid bilayer.
B) After it has been subjected to Gram staining, the cell should remain purple.
C) It has an outer membrane of lipopolysaccharide.
D) It is mostly composed of a complex, cross-linked polysaccharide.

Question

Quizplus · Accepted Answer

The bacterium described has characteristics of a Gram-negative bacterium, which includes having an outer membrane composed of lipopolysaccharides. This outer membrane helps in adherence to surfaces and protection against phagocytes, bacteriophages, and dehydration. The ability to survive boiling is not directly related to the cell wall composition but suggests a high level of resistance, possibly due to other cellular mechanisms. The lack of plasmids and relatively little peptidoglycan further supports the Gram-negative identification, as Gram-negative bacteria have less peptidoglycan than Gram-positive bacteria.

A Bacterium Has the Following Characteristics