What is a Virus?

• What are viruses considered to be?

  Organisms
• How do viruses reproduce?

  By using another organism's cell machinery
• What happens when a virus bursts a cell?

  New viruses find new cells to infect
• Why do viruses make us feel ill?

  They damage our bodies during infection
• What are three examples of viral diseases mentioned?

  • Measles
  • HIV
  • Tobacco mosaic virus
• How is the measles virus spread?

  By droplets from coughing or sneezing
• What are common symptoms of measles?

  Red rash and high fever
• Why is measles rare in the UK?

  Most people are vaccinated against it
• How is HIV primarily spread?

  Through sexual contact and bodily fluids
• What does HIV stand for?

  Human immunodeficiency virus
• What happens when someone first catches HIV?

  They may experience flu-like symptoms
• What is AIDS?

  A disease where the immune system is severely weakened
• What medications help people with HIV?

  Antiretroviral drugs
• What do antiretroviral drugs do?

  Prevent the virus from replicating
• What does the tobacco mosaic virus affect?

  Certain plant species like tobacco
• What is the appearance of leaves affected by tobacco mosaic virus?

  Discolored patches forming a mosaic pattern
• How does tobacco mosaic virus affect plant growth?

  It hinders photosynthesis and sugar production
• What is the main consequence of the tobacco mosaic virus on plants?

  Inadequate sugar production for growth
• What are the main symptoms of HIV infection?

  • Flu-like symptoms (fever, tiredness, aches)
  • Immune system damage over time
  • Unusual infections and cancers in advanced stages