Eubacteria and archaebacteria differ in their cell wall composition, membrane lipids, RNA polymerase structure, antibiotic sensitivity, and habitats. Eubacteria typically have peptidoglycan cell walls, contain ester linkages in their lipids, have a single type of RNA polymerase, are generally sensitive to antibiotics, and are widespread including in extreme environments. Archaebacteria lack peptidoglycan, have ether linkages in their lipids, have multiple RNA polymerases, are often resistant to antibiotics, and are typically found in extreme habitats like hot springs.

1. Differences between eubacteria and archaebacteria:
Characteristic Eubacteria Archaebacteria
Cell Wall
Composition Mostly peptidoglycan
Lack peptidoglycan, may have
pseudopeptidoglycan or other unique
structures
Membrane
Lipids
Contains ester linkages in
lipids Contains ether linkages in lipids
RNA Polymerase
Structure
Single type of RNA
polymerase Multiple types of RNA polymerase
Sensitivity to
Antibiotics
Generally sensitive to
antibiotics Often resistant to many antibiotics
Habitat
Widespread and found in
various environments,
including extreme conditions
Often found in extreme environments,
such as hot springs, salt flats, and deep-
sea hydrothermal vents
Metabolic
Diversity Diverse metabolic pathways Limited metabolic pathways
Genetic Diversity More genetically diverse Less genetically diverse
Introns in Genes
Usually contain introns in
genes Often lack introns in genes
Histones in
Chromosomes Histones are absent or few
Histones are present in some species,
helping to organize DNA
Examples Escherichia coli, Salmonella Methanogens, Halophiles, Thermophiles