infection and response

• What are pathogens?

  Microorganisms that cause disease
• What are the types of pathogens?

  • Bacteria
  • Viruses
  • Fungi
  • Protists
• What do bacteria produce that can cause disease?

  Toxins
• Name an example of a bacterium that causes disease.

  Salmonella
• How do viruses cause disease?

  By invading host cells and reproducing
• Name an example of a virus that causes disease.

  HIV
• What type of organisms can fungi cause diseases in?

  Plants and animals
• Name an example of a fungal disease.

  Rose black spot
• What are protists?

  Single-celled organisms
• How are protists often spread?

  By vectors
• Name a disease caused by a protist.

  Malaria
• How do pathogens spread?

  • Direct contact
  • Airborne transmission
  • Contaminated water
  • Vectors
• What is an example of a disease spread by direct contact?

  Influenza
• How can airborne pathogens spread?

  Through droplets from sneezes or coughs
• What is an example of a disease spread through contaminated water?

  Cholera
• What are vectors?

  Carriers that transmit pathogens
• Name a disease spread by a mosquito vector.

  Malaria
• What are the non-specific defences of the body?

  • Skin: Barrier to pathogens
  • Nose: Hairs and mucus trap particles
  • Trachea and Bronchi: Mucus and cilia remove pathogens
  • Stomach: Produces acid to kill bacteria
• What is the role of skin in the immune system?

  Acts as a barrier to pathogens
• How does the nose help defend against pathogens?

  Hairs and mucus trap particles
• What do mucus and cilia in the trachea and bronchi do?

  Remove pathogens
• What does the stomach produce to kill bacteria?

  Acid
• What are the functions of white blood cells?

  • Phagocytosis: Engulf and digest pathogens
  • Antibody production: Target antigens on pathogens
  • Antitoxin production: Neutralise toxins from bacteria
• What is phagocytosis?

  Engulfing and digesting pathogens
• What do antibodies target?

  Antigens on pathogens
• What do antitoxins do?

  Neutralise toxins from bacteria
• How does vaccination work?

  • Dead/inactive pathogens injected
  • Triggers immune response (antibody production)
  • Body creates memory cells for faster response
• What is injected during vaccination?

  Dead or inactive pathogens
• What is the purpose of memory cells in vaccination?

  For faster response to real pathogens
• What are the advantages and disadvantages of vaccination?

  Advantages:

  • Prevents outbreaks (herd immunity)

  Disadvantages:

  • Rare side effects
  • Not always 100% effective
• What do antibiotics do?

  Kill or inhibit bacteria
• Name an example of an antibiotic.

  Penicillin
• Why do antibiotics not work against viruses?

  Viruses have different structures
• What is a major issue with antibiotics?

  Overuse leads to resistance
• What is a solution to antibiotic resistance?

  Use only when necessary
• What do painkillers do?

  Relieve symptoms but do not kill pathogens
• Name an example of a painkiller.

  Paracetamol
• What are the stages of drug testing?

  1. Preclinical Testing: Cells, tissues, animals
  2. Clinical Trials:

  • Phase 1: Healthy volunteers
  • Phase 2: Patients
  • Phase 3: Large groups, double-blind trials

  1. Double-Blind Trial: Neither knows who receives drug/placebo
• What is tested during preclinical testing?

  Cells, tissues, and animals
• What is the focus of Phase 1 in clinical trials?

  Safety and dosage