Pathogens

• What are the four main types of pathogens?

  • Viruses
  • Bacteria
  • Fungi
  • Protists
• What is the life cycle of a pathogen?

  • Infect a host
  • Reproduce or replicate
  • Spread from the host to infect other organisms
• What are communicable diseases?

  Communicable diseases are diseases caused by pathogens that can be transmitted from one person to another.
• What is cystic fibrosis?

  Cystic fibrosis is an inherited genetic disorder that mainly affects the lungs, pancreas, liver, and intestine.
• What are deficiency diseases?

  Deficiency diseases develop because an organism does not have enough vitamins or minerals.
• How can diseases be transmitted?

  • Direct contact (e.g., shaking hands)
  • Water (e.g., dirty water)
  • Air (e.g., sneezing)
  • Unhygienic food preparation (e.g., undercooked food)
  • Vectors (e.g., organisms spreading disease)
• What is a vector in the context of disease transmission?

  A vector is any organism that can spread a disease.
• What’s a pathogen

  
  

  Pathogens are microorganisms that cause infectious diseases
• What is the primary function of the skin in human defense responses?

  It acts as a barrier to prevent bacteria and viruses from reaching underlying tissues.
• What happens when the skin is damaged or cut?


  The barrier is broken, leading to bleeding, and the body initiates a clotting process.
• What role do platelets play when the skin is cut?

  They set up a chain of events to form a clot that dries into a scab.
• What is the purpose of a scab?

  It forms a seal over the cut to stop pathogens from entering and prevents excessive bleeding.
• What does the skin produce to combat pathogenic bacteria?

  Antimicrobial secretions.
• How does healthy skin contribute to defense against pathogens?

  It is covered with microorganisms that help keep you healthy and act as an extra barrier.
• Why is the respiratory system considered a weak link in body defenses?

  It draws in air full of pathogens every time you breathe.
• What defenses do the respiratory and digestive systems have against pathogens?

  They have mechanisms to help prevent infections from occurring.
• What is the function of hairs and mucus in the nose?

  They trap particles in the air that may contain pathogens or irritate the lungs.
• What does blackened mucus indicate?


  It shows that the system is working to trap pollutants from the air.
• What do the trachea and bronchi secrete to trap pathogens?

  Mucus.
• How do cilia in the respiratory system function?

  They beat to waft mucus up to the back of the throat where it is swallowed.
• What role does the stomach play in the defense against pathogens?

  It produces acid that destroys microorganisms in swallowed mucus and pathogens in food and drink.
• What does the stomach acid destroy?

  Microorganisms in the mucus and the majority of pathogens in food and drink.