Primary non-specific defences against pathogens in animals

• What are the two types of defences against pathogens?

  Non-specific and specific defence mechanisms
• How do non-specific defence mechanisms function?

  They do not distinguish between types of pathogens but respond to them all in the same way
• What characterizes specific defence mechanisms?

  They distinguish between different types of pathogens and provide a rapid but longer-lasting response
• What is the function of skin as a barrier to pathogens?

  • Protective barrier/covering
  • Makes it difficult for pathogens to penetrate
  • Contains microorganisms that compete with pathogens for space
  • Produces sebum, which inhibits pathogen growth
• What happens if the skin barrier is compromised?

  The protective function is lost, making it easier for pathogens to infect the body
• What are the layers of the skin mentioned in the study material?

  Epidermis, dermis, and hypodermis
• what are primary and secondary non-specific defences?

  • physical barriers
  • inflammation and phagocytosis
• what are primary and secondary defences of specific defences?

  • Cell-mediated response - T-lymphocytes
  • Humoral response - B-lymphocytes
• What is the function of mucous membranes in the body?

  They cover, protect, and provide secretory and absorptive functions.
• How do mucous membranes help trap pathogens?

  They trap pathogens which are then cleared from vulnerable areas.
• In which environments are mucous membranes typically found?

  They are found in exposed environments such as airways and the digestive system.
• What role does hydrochloric acid in the stomach play in pathogen defense?

  It creates acidic conditions that are hostile to pathogens.
• Why is vaginal mucus important in preventing infections?

  It is acidic to prevent the entry of pathogens.
• What do tears and ear wax contain that helps protect against pathogens?

  They contain antibodies and lysozymes.
• What is the role of glands in the ear canal?

  They secrete ear wax or cerumen to trap pathogens.
• Why are cuts or abrasions in the skin a problem for pathogen entry?

  They allow pathogens to enter, making the body vulnerable to infection.
• What is the role of serotonin in blood clotting?

  Serotonin causes the smooth muscle in the walls of blood vessels to contract.
• How does serotonin affect blood vessels during the clotting process?

  It triggers contraction of smooth muscle in blood vessel walls, reducing blood flow.
• What is thromboplastin's role in blood clotting?

  Thromboplastin activates prothrombin to thrombin.
• What does thrombin do in the blood clotting process?

  Thrombin catalyzes the conversion of fibrinogen to fibrin.
• What is the role of fibrin in blood clotting?

  Fibrin forms a mesh that stabilizes the blood clot.
• What are cofactors and coenzymes in the context of blood clotting?

  Cofactors and coenzymes assist enzymes in the blood clotting process.
• How do proenzymes function in the blood clotting cascade?

  Proenzymes are inactive precursors that are activated during the clotting process.
• What is the significance of damaged tissue in the blood clotting process?

  Damaged tissue triggers the activation of platelets and the clotting cascade.
• What is the end product of the blood clotting cascade?

  The end product is a stable fibrin clot.