Ultra structure: Prokaryotes or Eukaryotes

On the basis of internal structure of cell of an organism, cells can be divided to prokaryotes and eukaryotes. Characteristics of cell are given in table.

Differences between prokaryote and eukaryotes

Prokaryotes                     Eukaryotes

Circular DNA in cytosol                Linear DNA in nucleus

No organelles                                  Several membrane bound organelles

Nucleoid                                          Nucleus

Single chromosome                        Several chromosome

Plasma membrane typically           Plasma membrane with receptors

lack receptors

Chemically complex cell wall       Chemically simple cell walls

DNA transcription and                   DNA transcription in nucleus and

mRNA translation occurs               mRNA translation in cystol

simultaneously

Flagellum simple                            Flagellum complex, built from

built from two proteins                  microtubules

May have pili and fimbriae            May have cilia

Haploid genome                              Diploid genome

May have plasmids                         Plasmids DNA not common

Compact genome (little                  Usually large amount of non-coding

repetitive DNA)                              and repetitive DNA

May have a glycocalyx cover        Glycocalyx only if no cell wall

Small ribosomes                             Large ribosomes in cystosol/nucleus

                                                          small ribosomes in organelles

No histones in chromosomes         DNA Wound around histones

Mycolaginous capsule                    No mycolaginous capsule

Cell size range 05-100mm             cell size range 10-150mm

A sexual reproduction                    Sexual reproduction