Microbiology Part 2

Microbiology Part 2

1. Describe what disinfectants, antiseptics, and antibiotics are and how they work

   • Disinfectants
     • These are usually quite strong substances
     • used on non living things
     • to reduce microbial growth
     • e.g Janola
   • Antiseptics
     • Applied to Skin
     • to reduce the amount of microbe numberes
     • e.g dettol
   • Antibiotics
     • are chemicals specifically designed by one organism to kill another
     • Discovered by Alexander Fleming
       • In 1928 Sir Alexander Fleming arrives home from 2 week holiday
         • left in sink petri dishes with bacteria in them
           • noticed that the mould was encircled by a ' clear yellow' substance
             • London was hit by cold spell- Fleming noticed Staphylococcus spread across plate except for the fungi secton
               • he deduced the mould released substance inhabited bacterial growth
                 • Discovered antibacterial substance not present in all molds
                   • Only in Penicillium notatum
     • Not effective against viral infections
       • antibiotics are designed to react to their allocated, particular bacteria

2. List some uses of microbes

   • Viruses
     • http://www.garlandscience.com/res/pdf/9780815341505_ch02.pdf
     • Gene Therapy
     • Cancer prevention and control
     • vaccines
     • Biological Pest Contrl
   • Bacteria
     • http://www.livestrong.com/article/29090-good-uses-bacteria/
     • Recycling Waste
     • Helps your digestion system
     • Treatment of sewage
     • Production of cheese and yoghurt
     • Insulin- breakdown of sugar
     • Pest control
   • Fungi
     • http://www.livestrong.com/article/174197-uses-of-fungus/
     • antibiotics e.g penicillin
     • Food e.g mushrooms, truffles
     • Bread Production- Yeast
     • Alcohol Production- fermentation
     • Used in Cheese- Moulds
     • Decompose- help break down rubbish
     • Dyes

3. Explain the differences between disinfectants, antiseptics, and antibiotics

   • Antibiotics
     • 1. to reduce bacterial to acceptable standards
       • or cease bacterial growth
         • or kill bacteria
   • Disinfectants
     • are not designed for living organisms
       • are used on inanimate things or surfaces
         • to stop or overall kill the microbes
   • Antiseptics
     • Applied to skin to reduce amount of bacterial growth
       • are cleansers

4. Discuss the effect of antibiotic resistance

   • http://www.tufts.edu/med/apua/about_issue/about_antibioticres.shtml
   • caused by people mot finishing the antibiotics prescribed to them from doctors
     • as they feel better and deem themselves healthy again
       • While most of the bacteria are destroyed the strongest and most resistant survive
         • They adapt to the antibiotics and are capable of withstanding the affects
           • They begin to reproduce
             • Which eventually leads to a SuperBug
               • It is possible for bacteria to loose their antibacterial resistance- although process is extremely slow
             • " Vertically" inheritance of antibacterial traits
               • or "horizontally"- bacteria exchange and swap genetic genes with others
         • selective pressure: only destroying susceptible bacteria, leaving stronger bacteria to grow and reproduce
     • Other two ways
       • http://www.tufts.edu/med/apua/about_issue/about_antibioticres.shtml
       • 1.genetic mutation
         • 1. some mutations cause bacteria to acquire chemicals (enzymes)
           • Which inactivates antibiotics
           • 2. Cause bacterium to destroy antibiotic's target objective
       • 2.gaining resistance from other bacterium
         • receive resistant genes from other bacterium
           • called conjugation
             • simple mating procedure that allows transfer of genetic code
               • can also be transported through viruses
                 • genetic qualities stored in virus's head
                   • qualities injected into the virus's victim