Non- Specific Responses

• What do glycoproteins in mucus contain?

  Long carbohydrate chains
• Why is mucus sticky?

  Due to long carbohydrate chains in glycoproteins
• What particles can mucus trap in the airways?

  Viruses, bacteria, pollen, and dust
• How are trapped particles moved in the airways?

  They are moved towards the throat by cilia
• What are cilia?

  Small hair-like structures on cells
• What is the function of motile cilia?

  To move mucus along the airway
• What triggers an expulsive reflex?

  Pathogen irritation of airway lining
• What are the two types of expulsive reflexes?

  Cough and sneeze
• What do coughs and sneezes expel?

  Air containing secretions and foreign particles
• What are lysozymes?

  Antimicrobial enzymes that break down bacteria
• Where are lysozymes found?

  In body fluids like blood and tears
• What does hydrochloric acid do in the stomach?

  Kills ingested bacteria
• How does mucus protect the gut?

  Prevents damage from hydrochloric acid
• How much of a human's weight is made up of bacteria?

  Roughly 1 kg
• What are examples of bacteria commonly found in humans?

  Candida albicans and E. coli
• Where do commensal microorganisms grow?

  On the skin, mouth, and intestines
• How do commensal microorganisms benefit humans?

  They compete with pathogenic microorganisms
• What can happen when antibiotics are used?

  They can kill friendly gut bacteria
• What happens when a pathogen evades the first line of defense?

  The second line of defense responds
• What does the second line of defense involve?

  Phagocytic cells and antimicrobial proteins
• What are the four categories of non-specific immune responses?

  • Physical: barriers like skin
  • Cellular: detection and ingestion of pathogens
  • Chemical: secreted substances against pathogens
  • Commensal organisms: competition with pathogens
• What comprises the first line of defense in humans?

  Skin, mucous membranes, expulsive reflexes, chemical secretions
• What is the role of keratin in the skin?

  Acts as a physical barrier to pathogens
• What do sebum secretions contain?

  Fatty acids with antimicrobial properties
• How does sweat contribute to pathogen defense?

  Leaves salt residue creating inhospitable conditions
• What do mucous membranes line?

  The gut, airways, and reproductive system
• What triggers blood clotting after a wound?

  Release of molecules from damaged membranes
• What is the end product of the blood clotting cascade?

  Fibrin forms a network trapping platelets

  
• What is inflammation?

  A local response to infection and tissue damage
• What role does histamine play in inflammation?

  Stimulates vasodilation and increases blood flow
• What do cytokines do?

  Trigger an immune response and inflammation
• What is the role of interleukins in inflammation?

  Promote inflammation and immune response
• What happens during wound repair?

  Stem cells divide to heal the wound

  
• What is granulation tissue?

  Tissue that fills the wound during healing

  
• What is the significance of non-specific immune responses?

  They provide a rapid response to all pathogens
• How do non-specific defenses respond to pathogens?

  They do not distinguish between different pathogens