Prokaryotes and Bacteria

• Cell Wall:

  Rigid outer covering made of peptidoglycan.
• Capsule:

  Protective slimy layer which helps the cell to retain moisture and adhere to surfaces.
• Plasmid:

  Circular piece of DNA.
• Flagellum:

  A tail like structure which rotates to move the cell.
• Pili:

  Hair-like structures which attach to other bacterial cells.
• Ribosomes:

  Site of protein synthesis.
• Mesosomes:

  Infoldings of the inner membrane which contain enzymes required for respiration.
• Viruses are non-living structures which consist of nucleic acid enclosed in a protective protein coat called the capsid, sometimes covered with a lipid layer called the envelope.