Biology: Gram Positive and Gram Negative Bacteria

What is a characteristic of the cell walls of Bacteria?

They contain a protein–carbohydrate complex called peptidoglycan

Which domain of organisms lacks peptidoglycan in their cell walls?

Archaea

What is a function of the peptidoglycan layer in bacterial cell walls?

To provide structural support

Which of the following is a characteristic of Gram-negative cell walls?

Outer membrane containing lipopolysaccharides Signup and view all the answers

What is a difference between bacterial and eukaryotic cell membranes?

Bacterial cells lack sterols and carbohydrates Signup and view all the answers

What is a characteristic that distinguishes eukaryotic from prokaryotic cells?

Presence of membrane-bound organelles Signup and view all the answers

What is the primary function of the cell wall in prokaryotes?

To prevent damage to the underlying protoplast Signup and view all the answers

What is the term for the carbohydrate 'backbone' of the peptidoglycan layer?

Glycan Signup and view all the answers

Which of the following is NOT a component of the cell envelope?

Ribosomes Signup and view all the answers

What percentage of the total dry weight of the cell does the cell wall constitute?

20% Signup and view all the answers

What is the term for the layer composed of a cross-linked polymeric mesh?

Murein layer Signup and view all the answers

What is the outermost layer of the cell envelope, if present?

Capsule or glycocalyx Signup and view all the answers

What is the main difference between the peptidoglycan layer in Gram positive and Gram negative bacteria?

The peptidoglycan layer is thicker in Gram positive bacteria Signup and view all the answers

What is the function of lipopolysaccharide in Gram negative bacteria?

It acts as a major constituent of the outer leaflet of the outer membrane Signup and view all the answers

What is the characteristic of the Gram negative cell wall?

It has a thin peptidoglycan layer Signup and view all the answers

What is the location of teichoic acid in Gram positive bacteria?

It is covalently linked to the peptidoglycan layer Signup and view all the answers

What is the difference between teichoic acid and lipoteichoic acid?

Teichoic acid is integrated into the peptidoglycan layer, while lipoteichoic acid is integrated into the cytoplasmic membrane Signup and view all the answers

What is the composition of the Gram negative cell wall?

Two membranes separated by a periplasmic space with a thin peptidoglycan layer Signup and view all the answers