Biology 3

• what are the four types of pathogen?


  Bacteria, virus, protist, fungi
• what does bacteria do?


  produced toxins that damage your cells and tissues
• what does virus do?


  reproduce rapidly replicate themselves, damage cells
• what do protist do?

  they are parasites they are often transferred to the organism by a vector.
• what are fungi and what do they do?


  Grow and penetrate human skin and the surface of plants causing diseases
• name three viral diseases

  Measles, HIV, tobacco mosaic virus
• what is measles and how is it spread?


  A viral disease spread by droplets from infected person sneeze or cough. people with measles develop a red rash and fever
• what is HIV and how is it spread?


  virus spread by sexual contact, or exchanging bodily fluids such as blood.

  flu like symptoms, attacks the immune cells
• what is tobacco mosaic virus and how is it spread?


  Virus affecting plants, causes a mosaic pattern on the leaves and discolouration
• what disease is caused by fungi?


  Rose black spot
• how does Rose black spot affect a plant?


  leaves die and drop-off meaning no photosynthesis can happen so the plan doesn’t grow very well
• how is rose back spot spread?


  Water and wind
• How can gardeners treat Rose black spot?


  fungicides and by stripping the plant or its affected leaves and destroying them
• what disease is caused by a protist?


  Malaria
• how is malaria spread and what are the symptoms?


  Malaria is spread by mosquito, causes fever can be fatal
• How can we prevent malaria?


  Bed nets, insect repellent, antimalarial medication.
• Name two bacterial diseases


  Salmonella and gonorrhoea
• what is salmonella?


  Food poisoning, causes fever stomach cramps vomiting and diarrhoea, chickens catch the disease and contaminate food to prevent they’re still vaccinated
• what is gonorrhoea?


  A sexually transmitted disease, caused by bacteria,, symptoms include pain whilst urinating yellow or green discharge and can be prevented by condoms
• name defence mechanisms the body has against pathogens


  Skin, hair and mucus in nose, trachea and bronchi, stomach producing hydrochloric acid
• if pathogen is due into the body how are they destroyed?


  The immune system destroys pathogen is using white blood cells
• What do white blood cells do to foreign cells?


  They engulf and digest them this is called phagocytosis
• what do antibodies do?


  antibodies are produced by white blood cells specifically to destroy an antigen
• How can a bacteria become resistant to antibiotics?


  they can mutate (Change)
• what three main stages are in drug testing?


  Preclinical, clinical trials, regulatory review.
• describe what happens in drug testing 


  Drugs are tested on humans cells and tissues in the lab, drugs are then tested on live animals, drugs are then tested on healthy volunteers who are split into two groups one is given the new drug the other one is given the placebo doctors assess and peer review the results