6.2.1 Non-Specific Immune Responses

• What is non-specific immunity?

  First line of defense
• The skin acts as a physical barrier
• Mucous membranes trap pathogens and prevent them from entering tissues.
• What substance in the stomach kills many ingested pathogens?

  Stomach acid
• Sweat contains antimicrobial peptides that help maintain the skin barrier.
• Saliva contains antimicrobial enzymes
• What are the physical barriers against pathogens in non-specific immunity?

  Skin and mucous membranes
• The skin is a waterproof barrier that prevents pathogen entry.
• Where are mucous membranes found in the body?

  Respiratory, digestive, reproductive tracts
• Lysozyme breaks down bacterial cell walls
• Match the chemical barriers with their functions:

  Stomach acid ↔️ Kills ingested pathogens

  Antimicrobial peptides ↔️ Maintain skin barrier

  Lysozyme ↔️ Breaks down bacterial cell walls
• Stomach acid is a chemical barrier that kills ingested pathogens.
• Where are antimicrobial peptides found in the body?

  Sweat
• What are the chemical barriers used by the body to defend against pathogens?

  Lysozyme, stomach acid, antimicrobial peptides
• Lysozyme in tears and saliva breaks down bacterial cell walls
• What is the role of stomach acid in defending against pathogens?

  Kills ingested pathogens
• Antimicrobial peptides in sweat help maintain the skin barrier.
• Match the chemical barrier with its function:

  Lysozyme ↔️ Breaks down bacterial cell walls

  Stomach acid ↔️ Kills ingested pathogens

  Antimicrobial peptides ↔️ Maintains the skin barrier
• Lysozyme is found in tears and saliva
• Stages of phagocytosis in the correct order:

  1️⃣ Chemotaxis

  2️⃣ Adherence

  3️⃣ Ingestion

  4️⃣ Digestion

  5️⃣ Exocytosis
• What attracts phagocytes to the site of infection during chemotaxis?

  Chemical signals
• Phagocytes bind to pathogens via surface receptors
• During digestion in phagocytosis, a phagosome fuses with a lysosome to form a phagolysosome.
• What role do macrophages play in phagocytosis?

  Ingest and destroy bacteria
• Non-specific immunity is present from birth
• Non-specific immunity acts broadly against various threats.
• Match the component of non-specific immunity with its function:

  Skin ↔️ Physical barrier preventing pathogen entry

  Mucous membranes ↔️ Trap pathogens and prevent tissue entry

  Stomach acid ↔️ Kills pathogens ingested with food
• What is non-specific immunity?

  First line of defense
• The skin acts as a physical barrier that prevents pathogen entry
• What do mucous membranes do in non-specific immunity?

  Trap pathogens
• Stomach acid kills pathogens ingested with food.
• How do tears contribute to non-specific immunity?

  Wash pathogens away
• Saliva contains antimicrobial enzymes that cleanse the mouth
• What does sweat contain that helps maintain the skin barrier?

  Antimicrobial peptides
• Non-specific immunity provides a broad, targeted response to infection.

  False
• What property of the skin allows it to prevent pathogen entry?

  Waterproof barrier
• Match the physical barrier with its function:

  Skin ↔️ Waterproof barrier

  Mucous Membranes ↔️ Trap pathogens
• Lysozyme breaks down bacterial cell walls
• Where is stomach acid found, and what is its function?

  Digestive system, kills pathogens
• Lysozyme in tears helps protect the eyes by breaking down bacterial cell walls.