Infection and response

• What are communicable diseases?

  Infectious diseases caused by pathogens that can be passed from one person to the other
• What is binary fusion?


  When bacteria is divided
• What is a virus?


  A small infectious agent that can replicate in every type of living organism
• What is bacteria?


  Freeliving organism often consisting of one biological cell
• What are the types of pathogens?

  bacteria, viruses, protists, fungi
• What is a pathogen?

  A microorganism that causes disease to its host
• Pathogen, transmission ,prevention ,symptoms and treatment :flu (influenza)

  Pathogen: virus

  transmission: air (droplets infection)

  prevention: face masks ,hands sanitiser, hand washing ,social distancing, isolation, vaccine (made with the antigens of the flu)

  Symptoms: Sneezing, sore throat, fever, nausea, headaches

  treatment: stay ,hydrated sleep
• Pathogens, transmission, prevention, symptoms, treatment: malaria

  Pathogen: protist

  transmission mosquitoes (they have the vector meaning they carry the disease)

  prevention quinine tablets, mosquito nets, vaccine, insect spray

  symptoms: fever

  treatment: hydration
• Pathogen, transmission, prevention, symptoms, treatment: measles


  Pathogen: virus

  transmission: air droplets

  Prevention, MMR vaccine (measles months and rubella)

  Symptoms: blisters that start in the mouth, rash, cough, fever, can cause meningitis

  treatment :stay hydrated and rest
• What role does the skin play in the bodies defence system?

  The skin is the bodies main physical defence system. It protects the body from physical damage and the hydration and it also protects and prevents entry of microorganisms. If the skin is cut platelets in the body clot at the sight of the wound. This stops microorganisms in the air or on the skin surface entering through the damaged surface
• What organs are lined by mucus membranes?

  Trachea, bronchi (in the lungs and nose)
• What does mucus do to help the bodies defence system?

  Mucus traps microorganisms in the passage ways so they don't get further in the body
• What do cillia do to help the bodies defence system?

  They move back and forth to help transport mucus and trapped microorganisms cross the membrane out of the body
• What enzyme do tears contain?

  lysozyme- which are able to kill bacteria by breaking them downs
• What are the bodies physical defences and what do they do?

  Blood: Contains platelets carried in blood plasma enable the blood to clot

  lungs: have mucus and cilia in the airway to trap and sweep organisms

  skin: forms and out a barrier to infection
• What are the bodies chemical defences and what do they do?

  Stomach: has hydrofluoric acid with a low pH to destroy microorganisms

  eyes: produced is the producing enzyme called

  Lyzomes that kill bacteria
• What are all of the bodies defence systems?

  Blood, lungs, skin, stomach, eyes
• What are macrophages?


  Type of white blood cell involved in the bodies non-specific defence system
• What do you macrophages do?

  Circulate in the blood and adapt to in digest and destroy microorganisms to a process called Phagocytosis
• What are examples of the bodies first line of defence and what does it do?

  Skin: physical barrier that stops pathogens from entering eyelashes: stop things entering your eyes

  mucus and cilia: trap dust/Pollen/pathogens

  sweat and tears: salt is not good for pathogen

  stomach acid: HCI has a pH of one to 2 which is too low for pathogens to survive

  earwax: traps pathogens

  platelets: blood clotting mechanism

  saliva: enzymes breakdown pathogens

  Sebum: anti-microbial substance

  urine: sterile substance
• What is the body second line of defence?

  White blood cells
• What do white blood cells do?(name all 3 steps)

  White blood cells sense engulf and then digest pathogens

  1) phagocytosis : macrophages/phagocyte sense then engulf then digest the pathogen

  
  

  2) produce antibodies: against the antigens of pathogen (this is a specific immunoresponse)

  
  

  3)Produce antitoxins: they neutralise toxins produced by bacteria
• Who made the first vaccine?

  Edward Jenner
• What does immune mean?

  Not being able to catch a disease again because you have antibodies in your blood to fight it
• How do vaccines work?

  In vaccines you put the antigens (which your body then produces antibodies from). This means that because you now have antibodies in your white blood cells will make antibodies very fast when you are in contact with the virus or disease
• What is heard immunity?

  When a large part of the population is vaccinated and everyone will then help others who can't get vaccinated so then people will have immunity so will protect others
• What is primary antibody response?

  When the antibody concentration rises gradually and peaks about two weeks after vaccination
• What is the secondary antibody response?

  The antibody concentration rises quickly and in the response is more intense. The antibody concentration remains higher for longer
• What happens when a vaccine is administered

  1)Vaccine is administered it contains weekend or dead for disease

  2) immune system identifies these foreign substances (pathogens) that have proteins called antigens on their surface

  3)once antigens are identified the immune system develops proteins that circulate in the blood these proteins are called antibodies. They fight the infection by killing the antigens. Antibodies are made by white blood cells known as lymphocytes

  4)The body remembers these antibodies so they are available to fight off the disease if exposed later on
• What are antibiotics?


  Medicine that kills stop the growth of bacteria
• Why would an antibiotic not work with the flu?

  The flu is a virus not a bacteria
• What do antibiotics do to bacteria?

  Destroy the cell wall and then stop the bacteria from multiplying
• What do painkillers do?

  Stop pain, stop fever
• What do antibiotics do?

  kill bacteria
• Why is it hard to destroy viruses?

  Viruses hide in host cells so they are hard to find and the outer coating is not effective
• Examples of painkillers


  Aspirin, paracetamol, ibuprofen, morphine
• Examples of antibiotics


  penicillin, amoxicillin
• If doctors over prescribe antibiotics what could happen to the pathogen?

  The pathogen will become more resistance antibiotics will become less effective this is known as antibiotic resistance
• In a graph why would the antibody concentration remain constant after a while e,g 28 days

  The immune system has fought the vaccine and is used to it and the white blood cells will still produce antibodies
• Vaccine or injections or drugs that contain what form of a pathogen that causes disease?

  Dead or altered