Prokaryotes

• What is the Ribosome?


  Consists of two subunits and contains RNA and proteins. Is the only organelle in the cell. They are smaller than in eukaryotes, as they are 70s
• What is the function of the ribosome?


  Synthesises polypeptides (proteins) and translates mRNA into proteins
• What is a plasmid?


  Small, circular piece of DNA. Multiple plasmids can exist in the same cell, and they carry at least one gene that is separate from their hosts.
• What is the function of a plasmid?


  They carry genes that enhance the organism's survival. They exist and replicate independently (self replicating), transmitting via sex pili between bacteria. This is also known as bacterial conjugation.
• What is a nucleoid (Genophore)?


  Is the genetic information of the cell. (DNA) It is always attached to the cell membrane and in direct contact with the cytoplasm. The DNA is typically double-stranded and circular in shape
• What is the function of the nucleoid (Genophore)?


  Controls activity of the cell, and is where transcription and replication takes place
• What is the cytosol?


  Water-base fluid within the cell
• What is the function of the cytosol?


  Allows the functions of life to take place and controls enzymes, signalling, and offers structural support.
• What is the cell membrane?


  Is semi-permeable, and is a thin and flexible barrier made of phospholipids, proteins and carbohydrates. There is a hydrophilic phosphate head on the outside and inside of the membrane, with a phospholipid tail on the inside of the membrane. This makes the plasma membrane amphipathic, meaning that it has polar and non-polar parts (the tails are nonpolar while the heads are.) Also contains enzymes that release ATP for active transport
• What is the function of the cell membrane?


  Regulates movement in and out of the cell and protects the cell. The proteins in the plasma membrane can open and close forming aqueous channels and in and out of the cell, and use ATP released from enzymes within the membrane to carry out active transport.
• What is the peptidoglycan cell wall?


  Made of peptidoglycan and surrounds the cell membrane
• What is the function of the peptidoglycan cell wall?


  Maintains the cell's shape, and protects it from damage or bursting if the internal pressure is high
• What is the slime capsule (glycocalyx) ?


  Is a thick polysaccharide layer surrounding the cell. They are anti-phagocytotic and have a negative charge.
• What is the function of the slime capsule (glycocalyx) ?


  Used for protection against desiccation (drying out) and phagocytosis, as their negative charge and smooth surface prevents the phagocyte from adhering to and engulfing the cell. Acts as a barrier between the cell and its environment.
• What is the flagella?


  Long, slender and hairlike and contains a motor protein
• What is the function of the flagella?


  The motor proteins spin/whip the flagella which propels the cell., typically through a liquid. (locomotion)
• What is the attachment pili?


  A hair-like extension on the outside of the cell. They are shorter than sex pili.
• What is the function of the attachment pili?


  Allows bacteria to adhere to each other or to available surfaces
• What is the sex pili?


  A hair like extension on the outside of the cell. They are longer than Attachment pili.
• What is the function of the sex pili?


  Allow for the exchange of genetic material, plasmids, via bacterial conjugations