Anaphy - finals

• Functions of the Lymphatic System

  • Fluid balance
  • Fat Absorption
  • Defense
• Lymph


  Fluid that enters lymphatic capillaries composed of water and some solutes
• Components of the Lymphatic System

  • Lymphocytes
  • Lymphatic vessels
  • Lymph nodes
  • Tonsils
  • Spleen
  • Thymus gland

  
• Lymphatic Capillaries


  • Carry fluid in one direction from tissues to circulatory system
  • Fluid moves from blood capillaries into tissue spaces
  • Tiny, closed-ended vessels
  • Fluid moves easily into capillaries
  • In most tissues
  • Join to form lymphatic vessels
• Lymphatic Vessels


  • Resemble small veins
  • Where lymphatic capillaries join
  • One-way valves
• Right lymphatic duct


  • Where lymphatic vessels from right upper limb and right head, neck, chest empty
  • Empties into right subclavian vein
• Thoracic duct


  • Collects lymph from the from remaining lymphatic vessels which do not enter the right lymphatic duct
  • Empties into left subclavian vein
• Tonsils


  • Palatine tonsils on each side of oral cavity
  • Pharyngeal tonsils near internal opening of nasal cavity (adenoid)
  • Lingual tonsils posterior surface of tongue
  • Form a protective ring of lymphatic tissue around nasal and oral cavities

  
• Lymph Nodes


  • Lymph moves through and immune system is activated (lymphocytes produced) if foreign substances are detected
  • Removes microbes by macrophages
• The Spleen


  • Size of clenched fist
  • Located in abdomen
  • Filters blood
  • Detects and responds to foreign substances
  • Destroys old red blood cells
  • Serves as a blood reservoir
• The Spleen


  • White pulp: lymphatic tissue surrounding arteries
  • Red pulp: contains macrophages and red blood cells that connect to veins
• The Thymus Gland


  • Bilobed gland
  • Located in mediastinum behind the sternum
  • Stops growing at age 1
  • At age 60 decreases in size
  • Produces and matures lymphocytes
• Immunity


  • The ability to resist damage from foreign substances
  • Can protect against microbes, toxins, and cancer cells

  
• Types of immunity


  • Innate
  • Adaptive

  
• Adaptive immunity


  • Defense that involves specific recognition to a specific antigen
  • Acquired after birth
  • Reacts when innate defenses don't work
  • Slower than innate immunity
  • Has memory
  • Uses lymphocytes (B and T cells)
  • 2 types antibody-mediated and cell-mediated

  
• Antigen


  • Substance that stimulates an immune response
  • Example—bacteria, virus, pollen, food, drugs

  
• Self-antigen


  Molecule produced by the person's body that stimulates an immune system response

  
• Antibody


  Proteins the body produces in response to an antigen
• Stem cells


  • Live in red bone marrow
  • Give rise to all blood cells
  • Give rise to some pre-T cells and pre-B cells
• Lymphocytes


  • Type of white blood cell
  • Involved in adaptive immunity
  • Develop from stem cells
  • Differentiate into specific lymphocytes such as B or T cells

  
• B cells


  • Type of lymphocytes
  • Involved in antibody-mediated immunity
  • Originate from stem cells
  • Mature in red bone marrow
  • Move to lymphatic tissue after mature
  • Lead to production of antibodies

  
• T cells


  • Type of lymphocyte
  • Involved primarily in cell-mediated immunity but also participate in antibody-mediated immunity
  • Mature in thymus gland
  • Move to lymphatic tissue after mature
  • 4 types
• Types of Adaptive Immunity

  • Naturally Acquired Immunity
  • Artificially Acquired Immunity

  
• Naturally Acquired Immunity - Active


  • Natural exposure to antigens causes production of antibodies
  • Can be lifelong immunity
  • Example—mononucleosis

  
• Naturally Acquired Immunity - Passive

  • Transfer of antibodies from mother to child
  • Example—breast milk or placenta
• Artificially Acquired Immunity - Active

  • Injection of antigens using vaccines which cause the production of antibodies
  • Immunization is a process of introducing killed, live, or inactivated pathogen
• Artificially Acquired Immunity - Passive

  • Injection of antibodies from another person or animal
• Artificially Acquired Immunity - Active


  • Live vaccines
  • Killed (inactivated) vaccines
• Live vaccines


  • Measles, mumps, and rubella (MMR) vaccine
  • Varicella (chickenpox) vaccine
  • Oral poliovirus (OPV) vaccine
  • Yellow fever virus vaccine
  • Live attenuated influenza vaccine
  • Smallpox vaccine
  • Rotavirus
• Killed (inactivated) vaccines


  • Whooping cough (pertussis) vaccine
  • Pneumococcal vaccine
• Artificially Acquired Immunity - Passive

  • Rabies immune globulin (RIG)
  • Tetanus Toxoid & Tetanus IG
• Innate immunity


  • Present at birth
  • Defense against any pathogen
  • Accomplished by physical barriers, chemical mediators, cells, inflammatory response

  
• Chemical mediators


  • Chemicals that can kill microbes and prevent their entry into cells
• Lysozyme


  Found in tears and saliva to kill bacteria
• Mucous membranes


  Prevent entry of microbes
• Histamine


  Promote inflammation by causing vasodilation
• Interferons


  Proteins that protect against viral infections by stimulating surrounding cells to produce antiviral proteins
• Cells of the Immune System

  • White blood cells
  • Phagocytic cells

  
• Phagocytic cells


  • Ingest and destroy foreign substances
  • Example—neutrophils and macrophages
• Neutrophils


  • First to respond to infection but die quickly