Salmonella is which type of bacteria?

Prepare for the ACVPM Food Protection Exam. Engage with an array of multiple choice questions, complete with hints and explanations. Equip yourself with the necessary knowledge to ensure a successful exam experience!

Multiple Choice

Salmonella is which type of bacteria?

Understanding how Gram staining works helps here. Salmonella has a thin peptidoglycan layer plus an outer membrane with lipopolysaccharide, which is the hallmark of Gram-negative bacteria. During staining, the crystal violet-iodine complex is washed out by alcohol in these organisms, and the cells take up the pink counterstain. That pink appearance classifies Salmonella as Gram-negative. It isn’t acid-fast, because acid-fast bacteria have waxy mycolic acids in their cell walls that resist decolorization and require a different stain. It’s also not Gram-variable, since Salmonella consistently shows a Gram-negative result.

Understanding how Gram staining works helps here. Salmonella has a thin peptidoglycan layer plus an outer membrane with lipopolysaccharide, which is the hallmark of Gram-negative bacteria. During staining, the crystal violet-iodine complex is washed out by alcohol in these organisms, and the cells take up the pink counterstain. That pink appearance classifies Salmonella as Gram-negative. It isn’t acid-fast, because acid-fast bacteria have waxy mycolic acids in their cell walls that resist decolorization and require a different stain. It’s also not Gram-variable, since Salmonella consistently shows a Gram-negative result.

More practice questions