B3: infection & response

• • PATHOGENS are MICROORGANISMS that enter; causing DISEASES
  • plants & animals can be infected by pathogens
• pathogens can cause COMMUNICABLE DISEASES— diseases that can SPREAD EASILY
• | bacteria

  • VERY SMALL CELLS which can reproduce rapidly inside our bodies
  • makes us sick by producing TOXINS that DAMAGE CELLS & TISSUES
• what does bacteria produce?

  toxins
• what do toxins do

  makes us feel ill
• what do toxins do

  damages our cells and tissues
• what are communicable diseases

  diseases that can easily spread
• what are pathogens

  microorganisms that cause disease
• | viruses

  • NOT CELLS!!!!!!!!!
  • they REPRODUCE RAPIDLY
  • lives inside cells & REPLICATE until the cell BURSTS, releasing the virus
  • this cell damage makes us feel sick
• are viruses cells?

  absolutely not
• how do viruses make us feel ill?

  replicate rapidly until cell bursts; letting out the new viruses. it’s the CELL DAMAGE that makes us feel ill
• | protists

  • SINGLE CELLED EUKARYOTES
  • some are PARASITES which live on/in other organisms & cause damage
  • they are transferred by a VECTOR which doesnt get the disease itself
• what are protists?

  single celled eukaryotes
• an example of a protist

  parasites
• how do parasites cause damage

  by living on or inside an organism
• how are protists transferred

  vector
• what’s a vector

  transfers a protist without getting the disease itself
• general example of a vector

  an insect
• | fungi

  • either SINGLE-CELLED or made of HYPHAE
  • hyphae can grow & PENETRATE HUMAN SKIN & SURFACE OF PLANTS, causing diseases
  • hyphae creates SPORES which can be spread to other plants & animals
• what are fungi?

  either single celled or made of hyphae
• how does hyphae make humans feel sick

  grow and PENETRATE HUMAN SKIN
• how does hyphae make plants affected by diseases

  penetrating through the surface of plants
• how can hyphae be spread

  through SPORES
• | how pathogens are spread

  • WATER: drinking or using dirty water
  • AIR: air borne particles when breathed in
  • (IN)DIRECT CONTACT: touching contaminated surfaces
• what are the 3 main ways in which pathogens are spread?

  water, air and direct contact