Types of Cells

• Prokaryotes


  Organisms without a cell nucleus or any other membrane-bound organelles
• Prokaryotes


  • Most are unicellular but some are multicellular
  • Examples: archaea, bacteria
• Eukaryotes


  Organisms whose cells are organized into complex structures by internal membranes and cytoskeletons
• Eukaryotes


  • Its most distinguishable character is the presence of true nucleus
  • Examples: fungi, animals, protists, plants
• Prokaryotes

  • Has DNA but no nucleus
  • Cytoplasm has no cytoskeleton or cytoplasmic streaming
  • Ribosomes are smaller size [70S (Swedberg's sedimentation rate)]
  • No membrane-bound organelles since there are no carbohydrates and they generally lack sterols
  • Cell size typically 0.2 to 2.0 μm (micrometer) in diameter
  • Flagella consists of two protein building blocks
  • Cell wall is usually present and is chemically complex (e.g. bacterial cell wall includes peptidoglycan)
  • Chromosomes are usually single circular chromosome that typically lacks histones
  • Cell division is through binary fission
  • No sexual recombination and can only transfer of DNA
• Eukaryotes


  Organisms whose cells have a nucleus and membrane-bound organelles
• Eukaryotes

  • DNA situated in the nucleus
  • Cytoplasm has a cytoskeleton and cytoplasmic streaming
  • Ribosomes are larger size (80S) but smaller size (70S) in its organelles
  • Has a cell membrane
  • Have membrane-bound organelles as it has sterols and carbohydrates that serve as receptors
  • Size typically 10 to 1000 μm in diameter
  • Has a flagella that is complex and consists of multiple microtubes
  • Cell wall are barely present and when they are, they are chemically simple (includes cellulose and chitin)
  • Multiple linear chromosomes with histones
  • Cell division includes mitosis
  • Sexual recombination includes meiosis
• Difference of Prokaryotes and Eukaryotes

  A) circular

  B) binary fission

  C) meiosis

  D) multicellular

  E) nucleoid

  F) bacteria

  G) protein

  H) human