Biology Topic 3: Infection and Response

• What are pathogens?

  Microorganisms that cause disease
• What do communicable diseases do?

  They can spread from one person to another
• How do viruses reproduce?

  They use the host cell's machinery
• What happens to a cell infected by a virus?

  The cell usually bursts, releasing new viruses
• How do some protists cause damage?

  They live on or inside other organisms
• What are fungi made of?

  Hyphae and sometimes single cells
• How do hyphae affect human skin?

  They can grow and penetrate the skin
• How can pathogens spread through water?

  By drinking or bathing in dirty water
• What is cholera?

  A bacterial infection spread by contaminated water
• How can airborne pathogens spread?

  Through droplets when coughing or sneezing
• What is athlete's foot?

  A fungal infection that causes skin irritation
• What is measles?

  A viral disease causing rash and fever
• How is measles spread?

  By droplets from sneezes or coughs
• What are complications of measles?

  Pneumonia and inflammation of the brain
• What is HIV?

  A virus spread by sexual contact
• What happens during the initial HIV infection?

  Flu-like symptoms occur for a few weeks
• What is tobacco mosaic virus (TMV)?

  A virus affecting many plant species
• How does TMV affect plants?

  It causes a mosaic pattern on leaves
• What causes malaria?

  A protist transmitted by mosquitoes
• How does rose black spot spread?

  Through water or by the wind
• How do mosquitoes contribute to malaria spread?

  They act as vectors for the protist
• What are symptoms of malaria?

  Repeating episodes of fever
• How can malaria spread be reduced?

  By stopping mosquitoes from breeding
• What is rose black spot?

  A fungus causing spots on rose leaves
• What is salmonella?

  A type of bacteria causing food poisoning
• What symptoms does salmonella cause?

  Fever, stomach cramps, vomiting, diarrhoea
• How can salmonella be contracted?

  By eating contaminated food
• What is gonorrhoea?

  A sexually transmitted bacterial disease
• What are symptoms of gonorrhoea?

  Painful urination and discharge
• How was gonorrhoea originally treated?

  With penicillin
• Why is gonorrhoea treatment becoming difficult?

  Strains of bacteria have become resistant
• How can hygiene prevent disease spread?

  By washing hands before food preparation
• How can vectors be controlled?

  By using insecticides or destroying habitats
• What does isolating someone with a communicable disease do?

  Prevents them from passing it on
• How do vaccinations work?

  They help the body produce antibodies
• What is the role of the skin in disease prevention?

  Acts as a barrier to pathogens
• How do hairs and mucus in the nose help?

  They trap particles containing pathogens
• What does hydrochloric acid in the stomach do?

  Kills pathogens that enter the body
• What is phagocytosis?

  Engulfing and digesting foreign cells
• What are antibodies?

  Proteins that lock onto invading cells