Question

multiple choice question
which generally reliable indicator of cell wall structure in bacteria is not informative when used in archaea?

• determination of teichoic acids
• presence of porins
• growth in hypotonic media
• the gram stain

Explanation:

The Gram stain is a reliable method to distinguish bacterial cell wall types (Gram - positive and Gram - negative) based on differences in peptidoglycan layers and cell wall structure. However, archaea have different cell wall compositions (e.g., pseudopeptidoglycan in some, or other unique components) that do not respond to the Gram - staining mechanism in the same way as bacteria. Teichoic acids are specific to Gram - positive bacteria, porins are related to Gram - negative bacterial outer membranes, and growth in hypotonic media relates to cell wall integrity in general (but the Gram stain is the key indicator for bacterial cell walls that fails for archaea).

Answer:

the Gram stain