Question

A Gram-positive bacterial cell has a thick layer of peptidoglycan, contains unique ______ called teichoic acids, and appears _____.

A) Enzymes, blue
B) Proteins, red
C) Lipids, green
D) Polymers, purple

Answer 1

The unique molecules called teichoic acids are polymers found in the cell wall of Gram-positive bacteria, which appear purple after Gram staining.

Step-by-step explanation:

The Gram-positive bacterial cell contains unique polymers called teichoic acids, and appears purple when stained during the Gram staining procedure. Teichoic acids are embedded within the thick peptidoglycan layer of Gram-positive bacteria and contribute to the cell wall's rigidity and the bacteria's ability to cause infection.

By contrast, Gram-negative bacteria have a relatively thinner peptidoglycan layer and an additional outer membrane containing lipopolysaccharides. The correct answer to the question is therefore "D) Polymers, purple."