Prokaryotic v Eukaryotic Cells (AQA A Level Biology): Revision Note

Comparing prokaryotic and eukaryotic cells

• There are many comparisons that can be made between the structures and processes of prokaryotic compared to eukaryotic cells

  Feature	Prokaryotes	Eukaryotes
  Size	0.5–5 µm diameter	Up to 100 µm diameter
  Genome	DNA is circular with no proteins, in the cytoplasm	DNA is associated with histones (proteins), forming chromosomes
  Cell division	Occurs by binary fission, no spindle involved	Occurs by mitosis or meiosis and involves a spindle to separate chromosomes
  Ribosomes	70S ribosomes	80S ribosomes
  Organelles	Very few, no membrane-bound organelles	Numerous types of organelles are membrane-bound. Single membranes: lysosomes, Golgi complex, vacuoles. Double membranes: nucleus, mitochondria, and chloroplast. No membrane: ribosomes, centrioles, microtubules
  Cell wall	Made of peptidoglycan (polysaccharide and amino acids) and murein	Present in plants (made of cellulose or lignin) and fungi (made of chitin, similar to cellulose but containing nitrogen)