Basis of differentiation | Bacteria | Eukaryotes |
Piody | Haploid | Diploid |
Genetic reassortment | Infrequent short gene conversion and horizontal gene transfer events | Homologous recombination and chromosome segregation linked to reproduction |
Origin | Bacteria were colonized and abundant for over a billion years before eukaryotes existed | Eukaryotes originated approximately 1-1.5 billion years after prokaryotes |
Size | Most bacterial cells are extremely small (1 micrometer in diameter) | Eukaryotic cells range from 10-100 micrometers in size |
Ribosomes | Bacteria have 70 S ribosomes | Eukaryotes have 80 S ribosomes |
Modification of RNA | No mRNA modifications occur in bacteria | mRNA modifications occur after transcription |
Transcription and translation | Transcription and translated are coupled in bacteria | Transcription and translation occur individually in eukaryotes |
Introns and repetitive sequences | Introns and repetitive sequences are not present in bacteria | Introns and repetitive sequences are present in bacteria |
Initiation of protein synthesis | Protein synthesis of bacteria is initiated by formyl-methionine | Protein synthesis is initiated by methionine |
Internal compartments | Bacteria do not contain any internal compartments or an internal membrane system | Eukaryotes contain internal compartments and an internal membrane system |
Reproduction | Bacteria produce asexually (binary fission) | Mitosis occurs in eukaryotes |
Chromosomes | Single circular DNA is present in bacteria | Proteins and DNA are complexed to form multiple chromosomes |
Flagella | Some bacterial cells contain a simple flagella that are made out of a single fiber of flagellin protein | Some eukaryotes have a complex flagella and cilia with a structure of 9+2 arrangement of microtubules |
Unicellular or multicellular | All bacterial cells are unicellular | Eukaryotes can either be unicellular or multicellular |