Infection & response

• What are pathogens?

  Microorganisms that cause disease
• What type of diseases do pathogens cause?

  Communicable diseases that can spread easily
• Can both plants and animals be infected by pathogens?

  Yes, both can be infected
• How small are bacteria compared to body cells?

  About 1/100th the size
• How do bacteria make you feel ill?

  By producing toxins that damage cells
• Are viruses considered cells?

  No, they are not cells
• How small are viruses compared to bacteria?1/100th the size of bacteria
• How do viruses replicate inside the body?

  By using the host cell's machinery
• What happens to the host cell after a virus replicates?

  The cell usually bursts, releasing viruses
• What are protists?

  Single-celled eukaryotes
• How do some protists cause damage to organisms?

  By living on or inside them as parasites
• What are fungi made up of?

  Hyphae, which are thread-like structures
• How can hyphae affect human skin and plants?

  By growing and penetrating them, causing diseases
• How do fungi reproduce?

  By producing spores that spread
• What are the main ways pathogens can be spread?

  • Water: Contaminated drinking or bathing water
  • Air: Droplets from coughs or sneezes
  • Direct contact: Touching contaminated surfaces
• How is cholera spread?

  By drinking contaminated water
• How are airborne pathogens spread?

  Through droplets from coughs or sneezes
• What is athlete's foot?

  A fungal infection that causes skin itching
• How can athlete's foot be spread?

  By touching contaminated surfaces
• What is measles?

  A viral disease causing a red rash
• How is measles spread?

  By droplets from sneezes or coughs
• What complications can arise from measles?

  Pneumonia and inflammation of the brain
• How are people vaccinated against measles?

  When they are young
• What are the symptoms of measles?

  Red rash and high fever
• What is HIV?

  A virus spread by sexual contact
• How does HIV initially affect a person?

  Causes flu-like symptoms for weeks
• How can HIV be controlled?

  With antiretroviral drugs
• What does HIV attack in the body?

  The immune cells
• What is late-stage HIV infection known as?

  AIDS
• What is tobacco mosaic virus (TMV)?

  A virus affecting many plant species
• What symptom does TMV cause in plants?

  Mosaic pattern on leaves
• How does TMV affect plant growth?

  Reduces photosynthesis efficiency
• What is rose black spot?

  A fungus causing spots on rose leaves
• What happens to leaves affected by rose black spot?

  They turn yellow and drop off
• How does rose black spot spread?

  Through water or by the wind
• How can gardeners treat rose black spot?

  Using fungicides and removing affected leaves
• What is malaria caused by?

  A protist
• Where does part of the malarial protist's life cycle occur?

  Inside the mosquito
• How do mosquitoes spread malaria?

  By inserting the protist into blood vessels
• What are the symptoms of malaria?

  Recurring episodes of fever