Microbiologists Use the Gram Stain to Aid in Identification of Bacteria

Multiple Choice

Microbiologists use the Gram stain to aid in identification of bacteria. What is the major difference between Gram- positive and Gram- negative bacteria?

A) presence or absence of muramic acid in the cell wall
B) presence or absence of peptidoglycan in the cell wall
C) presence or absence of outer membrane
D) structure of the lipids in the plasma membrane