Question

Which of the following is absent in Gram- negative bacteria and present in Gram- positive bacteria?

(a) Teichoic acids

(b) Periplasmic space

(c) Outer membrane

(d) Lipopolysaccharide

This question was posed to me by my school teacher while I was bunking the class.

My question is taken from Two Fundamentally Different Classes of Cells in chapter Introduction to Cell of Cell Biology

Answer 1

The correct answer is (a) Teichoic acids

Explanation: Teichoic acids are present in Gram positive and absent in Gram negative bacteria and they stain purple by Gram stain. Periplasmic space and outer membrane are present in Gram negative while they are absent in Gram positive bacteria. Lipolysaccharide content is high in Gram negative and almost none in Gram positive.