Infection & response

• How can pathogens be spread in animals & plants

  • Water -pathogens can be pick up Drinking dirty water e.g cholera
  • Air - pathogens can be carried in air & can be breathed in
  • Direct contact- by touching contaminated surfaces, including the skin
• Pathogens - microorganisms that cause infectious diseases
• How to prevent or reduce spread of diseases

  • Being hygienic e.g washing your hands
  • Destroying vectors - getting rid of organisms that can spread diseases
  • Isolating, someone that has a disease so they cannot spread it on
  • Vaccinations- vaccinating animals & people could make them less likely to have these diseases
• Non-communicable diseases - caused by a pathogen & cannot spread from person to person
• Communicable diseases - caused by a pathogen & can be spread from person to person
• virus diseases

  • measles
  • hiv
  • Tobacoo
• Bacterial Diseases

  • Salmonella
  • gonorrhea
• Fungal diseases

  • Red black spot
• protist diseases

  • Malaria
  • protist
• Human body against pathogens

  • Skin acts as a barrier against pathogens & secrets anti microbial substances, which kill pathogens
• Human body against pathogens

  • Nose - hair & mucus in your nose, traps, any particles that could contain pathogens
• Human body against pathogens

  • Trachea & bronchi secrete mucus to trap pathogens
• Human body against pathogens

  • Stomach-produces hydrochloric acid which kills pathogens
• Immune system against pathogens

  • If a pathogen enters your body, your immune system will try to destroy it
• White blood cells against pathogens

  • phagocytosis engulf & digest the foreign cells
• White blood cells against pathogens

  • Antibody a blood protein produced in response to & counteracting a specific antigen
• White blood cells against pathogens

  • Antitoxin counteract toxins produced by invading bacteria
• Vaccination involves introducing small quantities of dead or inactive forms of a pathogen into the body to stimulate the white blood cells to produce antibodies. If the same pathogen re-enters the body the white blood cells respond quickly to produce the correct antibodies, preventing infection.
• Medicine used to treat diseases

  • Antibiotics (penicilli) which kill the infective bacteria
• Medicine used to treat bacteria

  • Painkillers (paracetamol etc) only treat the symptoms of disease, but do not kill the pathogen
• Different antibiotics kills different types of bacteria so it is important to be treated with the right one
• However, the emerge of strain resistant to antibiotics is a great concern
• Preclinical - testing drugs in the lab using cells tissues & live animals
• Pre-clinical process

  • effcacy to see if the products works & how effective it is
  • Toxicity to see how harmful it is
  • Dosage to see the concentration that needs to be given & how often
• Clinical testing is used on healthy, volunteers & patience
• clinical testing

  • Low-dose is given to a healthy volunteer
  • If it is safe further testing is done on a patient suffering from the illness
  • The optimum dosage is found
  • Split into two groups to find out how well the drugs work
  • One is given a new drug & Is given placebo
  • Therefore the doctor can see the difference the drug makes
• virus disease - measles

  • spread by inhalation of droplets from sneezes & coughs
  • it shows symptoms of fever & red skin rash
  • Most children are vaccinated against measles
• virus disease - HIV

  • spread by sexual contact or exchange
  • initially causes flu like symptoms
  • could be prevented by using contraceptives e.g condom
• virus disease - tobacco

  • effects plants
  • its causes the plant to become discoloured
  • the plant cannot carry out photosynthesis as well
• fungal disease - rose black spot

  • black or purple spots on leaves of rose plants & could turn yellow & drop off
  • spread by the environment through water or wind
  • can be treated by fungi and by stripping the plant of its affected leaves
• bacterial diseases - salmonella

  • spread by bacteria ingested in food or prepared in unhygienic conditions
  • causes vomiting, cramps, fever or diarrhoea
  • treated by vaccinating poultry (chicken)
• bacterial disease -goharrhoea (std)

  • spread by sexual contact
  • causes thick yellow or green discharge to vagina or penis
  • treated with antibiotics, penicillin or using contraceptive
• protist - malaria

  • spread by mosquitos
  • causes fever & can be fatal
  • can be treated by preventing the vector, from breeding & avoid being bitten
• respiration - the process of transferring energy from glucose which goes on in every cell
• respiration is an exothermic reaction which is continuously occurs in living organisms
• aerobic (with oxygen)

  • uses glucose
  • produces carbon dioxide & water
  • exo reaction
  • transfer & released energy
  • transfer larger amounts of energy
• anaerobic (without oxygen)

  • uses glucose
  • produces lactic acid
  • transfer & release energy smaller than aerobic
• anaerobic occurs when their is not much oxygen so in times of intense exercise
• when doing vigorous exercise your body requires more energy from respiration. Anaerobic produces lactic acid in the muscles. The lactic acid is transported to liver to be converted into glucose your breathing, breath volume & heart rate all increase