Disease, defence and treatment

• What causes communicable diseases?

  Spread of micro-organisms
• What are pathogens?

  Micro-organisms that can cause harm
• What are the four main types of pathogens?

  • Virus
  • Bacterium
  • Fungus
  • Protist
• What is the life cycle of a pathogen?

  Infect a host, reproduce, spread, infect
• What are communicable diseases?

  Diseases transmitted from one person to another
• What features do all bacterial cells have?

  • No nucleus
  • Cell wall made of murein
  • Cell membrane and cytoplasm
  • Loose chromosome in a long loop
  • May contain plasmids
  • No chloroplasts or mitochondria
  • Exist as single cells
  • May have a slime capsule
  • Divide by binary fission
  • May have pili or flagella
• Why are viruses not considered alive?

  They do not complete all life processes
• What is the genetic material of a virus made of?

  Short length of DNA
• What surrounds the genetic material of a virus?

  A protein coat
• How do pathogens adapt to complete their life cycle?

  They have structural adaptations for survival
• What is the role of pili in bacterial cells?

  To attach to surfaces
• What is the function of flagella in bacterial cells?

  To allow movement
• What process do bacterial cells use to divide?

  Binary fission
• What is the purpose of a slime capsule in bacteria?

  To prevent drying out
• What is the structure of a virus?

  Genetic material surrounded by a protein coat
• What is the significance of strains in viruses?

  Strains refer to variations, not species
• What is the main function of micro-organisms in the gut?

  Help with digestion
• How do micro-organisms recycle nutrients?

  By decaying dead organisms
• What is the relationship between pathogens and communicable diseases?

  Pathogens cause communicable diseases
• What is the role of the immune system in disease prevention?

  It defends against pathogens
• What is the definition of a host?

  An organism lived on or in by a parasite
• What is the definition of an organism?

  A living entity, e.g., animals or plants
• What is the significance of the cell wall in bacterial cells?

  It provides structure and protection
• What is murein?

  A component of bacterial cell walls
• What is the difference between murein and cellulose?

  Murein is in bacteria, cellulose in plants
• What do plasmids contain?

  Small loops of DNA
• What is the role of the chromosome in bacterial cells?

  It carries genetic information
• What is the cytoplasm?

  The gel-like substance inside cells
• What is the function of the cell membrane?

  It controls what enters and exits the cell
• How do the features of bacterial cells contribute to their survival?

  They have adaptations for various environments
• What is the importance of studying the immune system?

  To develop treatments for diseases
• What is the role of antibiotics?

  To kill or inhibit bacterial growth
• What is antibiotic resistance?

  When bacteria evolve to survive antibiotics
• How does the discovery of new drugs impact disease treatment?

  It provides new options for combating diseases
• What are monoclonal antibodies used for?

  Medical treatments and diagnostics
• What is the significance of the immune system in health?

  It protects against diseases
• How do micro-organisms contribute to nutrient recycling?

  By breaking down dead organisms
• What is the relationship between micro-organisms and human health?

  Most are harmless or beneficial
• What is the role of the gut microbiome?

  To aid in digestion and nutrient absorption
• What is the function of the immune response?

  To identify and eliminate pathogens