Disease defence and treatment

• What is a micro-organisms?

  Tiny Organism that are bacteria, fungi, virus or protist, only be seen by a microscope.
• What do we call microorganism that causes disease?

  Pathogens
• Ways microorganism are useful

  Reducing infection, medicine, making yoghurt and cheese, important decomposer
• What do bacteria release in our bodies that make us feel ill?

  Toxins
• What do viruses do inside our bodies?

  Reproduce in the cell
• Bacteria Cell

  Cell membrane, Cytoplasm, DNA is loose in the cytoplasm as bacteria, cell wall (made by murein), flagella=movement
• Virus

  Nucleic Acid, Protein Coat, Membrane envelope, Spikes (allows virus to get into cell and invades)
• Description of Bacteria

  Large, single cell, living, reproduce by splitting
• Description of Virus

  Small, protein coat and genetic material, not living, reproduce by invading host cells
• Aseptic Technique


  Technique to grow specific sample of bacteria this keeps other bacteria's away and not to contaminate.
• Process of growing microorganism

  1. flame the wire loop to remove any microorganism that are present 2. Let it cool by holding near Bunsen flame 3. Put the wire loop into milk sample to collect a small amount 4. Lift the lid of agar plate, enough insert the loop and gently streak surface of agar with the loop 5. Replace lid quickly so microorganism from air get in 6. Put the loop back in the Bunsen Burner to sterilise 7. Tape across the lid of Agor enough to stop it open but not completely seal it as oxygen can still get in 8. Place the plate around in an incubator at 24 degrees
• Why do we keep food in the fridge or freezer?

  It does not kill but slows and prevent the growth of bacteria/fungi
• Why do we cook food?

  It kills the bacteria
• What is Penicillin?

  It is a antibiotic that is used to treat bacterial infection
• Give some of the condition that you need in the fermenter to help penicillin fungus grow?

  Nutrients going in, Sterile air supply, Temperature and pH
• What is communicable disease?

  Microorganisms cause the communicable disease which means the disease to spread
• HIV/AIDS - Virus

  How is it spread- body fluids (e.g blood semen and Virginal fluid) Symptoms - HIV effects white blood cells of the immune system. Over time a person is unable to fight infection. Reducing the risk of infection- Using a condom, don't share needles, wearing gloves when treating bleeding
• Chlamydia- Bacteria


  How is it spread- Unprotected Sex, Symptoms- causes pain urinating, unusual discharge, infertility, Reducing the risk of infection is using a condom
• Malaria- Protist

  How is it spread- By mosquitoes, Symptoms- Affects red blood cells and liver causes high temp, headache, vomiting. Reducing the risk of infection- Antimalaria tablets, prevents mosquitoes, nets repellent cream
• The first line of defence

  Skin, Tears, Saliva, Glia (little hairs in the trachea) Mucus, Hydrochlric acid in the stomach, blood clots
• Scabs


  The skin forms a barrier to stop pathogens from entering. However, if we have to cut a blood clot form to seal the open skin to prevent entry to microbes.
• The second line of defence

  White blood cells follows the chemical signals from the bacteria. Phagocyte engulfs the bacteria. Once inside the bacteria is broken down by enzymes
• What are memory cells and why are they important?

  Pathogens enter the body. Memory cells recall diseases and produce antibodies. Immune cells become resistant after this process.
• Who invented the vaccine

  Edward Jenner
• What disease did milkmaids commonly catch

  Cowpox
• Whats inside a vaccine?

  Contains dead/weakened antigens of a pathogen
• Why are people vaccinated?

  Become immune (not becoming ill) to many different bacterial and viral conditions
• Process of a vaccine

  1. A vaccine contains dead/inactive pathogens 2. these inactive pathogens are injected 3. the antigens in the vaccine stimulate white blood cells to make antibodies 4. the antibodies destroy the pathogens and memory white blood cells are produced 5. the real pathogens invades your body 6. your memory white blood cells recognises the pathogens, make antibodies quickly and in large numbers to destroy if before you are ill
• What is herd immunity?

  Most of the population gets immunized, spread of contagious diseases is contained
• Antibodies What are they?

  Proteins that are often chemically modified and are semi syrthemic
• Antibodies What are the problems?

  Over prescription can lead to antibodies resistance
• Antibodies are there any rules/ important advice?

  Must complete full core of medication, do not share only when neccessary
• Antibodies What are they used to treat?

  Bacterial infection
• Can you name any examples of Antibodies

  Penicillin and tetracyline
• What is a drug?

  Chemical that alters the way the body works in certain ways
• What makes a good medicinal drug?

  Effective- prevents or cure the disease, Safe- must not be toxic, no unacceptable side effects, Stable- medicine must be able to be stored, Successfully taken into and removed from the body
• The stage of drug testing?

  The drug is tested on human cells grown in the laboratory. The drug is tested on animals to look for side effects. The drug has a clinical trial-it is tested on healthy volunteers. Further clinical trials look at the optimum dose of the drug. The drug is trialled on people who have had the disease to see if it is successful. If these test are passed the drug is licensed for general use.