Your SlideShare is downloading. ×
  • Like
Lymphatic system
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×

Now you can save presentations on your phone or tablet

Available for both IPhone and Android

Text the download link to your phone

Standard text messaging rates apply

Lymphatic system

  • 838 views
Published

Typed-up notes taken during the PowerPoint in class.

Typed-up notes taken during the PowerPoint in class.

Published in Education
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
838
On SlideShare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
27
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Lymphatic System
  • 2. Purpose
    • Transports excess fluids into blood stream
    • Absorbs fats in the small intestine
    • Helps defend body against diseases and their causing agents
  • 3. Lymphatic Capillaries
    • System begins as capillaries
      • End in the subclavian veins of the thorax
    • Closed-ended tubules
    • Extend into interstitial spaces
      • Spaces/fluid spaces between tissues and cells
    • Lymph is the fluid which has entered the lymph capillaries
  • 4. Lymphatic Vessels
    • Walls are thinner than veins
    • Contain semilunar valves to prevent backflow
    • Leads to specialized organs called lymph nodes
  • 5. Collecting Ducts
    • Lymphatic vessels drain into lymphatic trunks which drain into one of two collecting ducts
    • Thoracic duct
      • Larger and longer of the two
      • Begins in abdomen
      • Empties into left subclavian vein
    • Right lymphatic duct
      • Empties into right subclavian vein
  • 6. Lymph
  • 7. Lymph Formation
    • Capillary blood pressure filters water and small molecules from the plasma
    • Interstitial hydrostatic pressure increases the forces the fluid into the lymphatic capillaries
    • Lymph formation prevents edema (build up of excess tissue fluid)
  • 8. Lymph Function
    • Returns small molecules and fluids to the blood stream
    • Transports foreign particles to the lymph nodes, including:
      • Bacteria
      • Viruses
  • 9. Lymph Flow
    • Movement of lymph is caused by
      • Contracting skeletal muscles
      • Deep breathing
    • Lymph flow peaks during physical exercise
    • Removal of lymphatic tissue can cause edema
      • However, it prevents the spread of cancer cells
  • 10. Lymph Nodes
  • 11. Lymph Nodes
    • Located along lymphatic pathways
    • Contain large numbers of lymphocytes and macrophages
      • They fight invasions of foreign and harmful particles
  • 12. Lymph Node Structure
    • Bean shapred
    • Less than an inch long - ~2.5 cm
    • Hilum – the indented region of the node
    • Vessels lead to:
      • Afferent vessels lead to the node
      • Efferent vessel leaves at the hilum
    • Capsule divides into modules
      • Contains masses of lymphocytes and macrophages
      • Spaces where the lymph can flow through the node
  • 13. Lymph Node Location and Function
    • Grouped in chains along the larger lymphatic system/vessels
    • Absent in the central nervous system
    • Two primary functions
      • Filter potentially harmful particles from the lump before returning it to the blood
      • Centers of lymphocyte production
    • Macrophages in the lymph nodes engulf foreign particles
  • 14. Other Lymphatic Organs
    • Thymus
      • Larger during infancy and early childhood
        • Shrinks during puberty
      • Contains thymocytes developed in the red bone marrow
      • Some mature into T-lymphocytes
          • These leave the thymus and provide immunity
    • Spleen
      • Largest of the lymphatic organs
      • Resembles an overlarge lymph node
  • 15. Defense Against Infections
  • 16. Defense System Against Infections
    • Pathogen – a disease causing agent (infection)
      • Bacteria
      • Fungi
      • Virus
        • Not “living”, as it cannot procreate on its own and has to infect another cell in order to reproduce
    • Innate Defenses – nonspecific defenses
    • Adaptive Defenses – specific defenses
      • Immunity
  • 17. Innate Defenses (Nonspecific)
    • Specific Resistance – diseases are unique to a species
      • (i.e. measles, mumps, gonorrhea, syphilis)
    • Mechanical barriers – first line of defenses
      • Skin
      • Mucous membranes in respiratory, digestive, urinary, and reproductive passageways
    • Chemical barriers, including:
      • Enzymes (gastric juices, tears, ect)
      • Salts in perspiration
    • Fever – raises brain’s set point to a higher temperature
    • Natural Killer (NK) cells – a type of lymphocyte
      • Protect body from viruses and cancer
      • Secret perforins which disintegrate cells
    • Inflammation – white blood cells accumulate at site of infection/invasion
    • Phagocytosis – removal of foreign particles
      • Neutrophils, monocytes become macrophages
  • 18. Adaptive Defenses – Immunity (Specific)
    • Immune response distinguishes between “self” and “not-self”
    • Antigens = molecules that trigger immune response
    • Carried out by lymphocytes and macrophages
    • Before birth your cells inventory proteins and other large molecules of the body as “self”
    • Receptors on lymphocytes enable cells to recognize foreign antigens
  • 19. Lymphocytes
  • 20. Lymphocyte Origins
    • T-Lymphocytes
    • Leave bone marrow as undifferentiated lymphocytes
    • 70-80% of circulating lymphocytes
    • Reside in:
      • Lymph nodes
      • Thoracic duct
      • White pulp of the spleen
    • B-Lymphocytes
    • Thought to reside in the bone marrow until differentiation
    • 20-30% of circulating lymphocytes
    • Reside in:
      • Lymph nodes
      • Spleen
      • Bone marrow
      • Intestinal lining
  • 21. Lymphocyte Function
    • T-Cells
    • Attach to antigen bearing cells  cellular immune response
    • Release cytokines (i.e. interleukins) which cause a cellular response to antigens
    • Release toxins which kill target cells
    • B-Cells
    • Differentiate into plasma cells and produce antibodies
    • Humoral reponse (fluids)
    • Up to 2000 antibodies per second
    • Antibodies travel through fluids to destroy antigens
    • T-Cells and B-Cells both:
    • Respond to recognized antigens and create clones of themselves
    • Have millions of varieties
      • Each variety responds to a specific antigen
  • 22. T-Cells
    • Activation requires an antigen presenting cell
      • Macrophages, B-cells, ect
    • Helper T-Cells
      • Stimulate B-cells to produce antibodies
      • CD4 helper T-cells largest target of HIV
    • Cytotoxic T-Cells
      • Watch for cancerous and virally infected cells
      • When activated:
        • proliferates and creates more clones
        • binds and releases more perforins to cut open antigen bearing cells
    • Memory T-Cells
      • Responds to a second exposure of an antigen and immediately becomes a cytotoxic T-cell
  • 23. B-Cells
    • Activated when it fits an antigen that fits its antigen receptors
      • Immediately divides repeatedly
        • Most need helper T-cell cytokines to stimulate clone proliferation
    • Some B-cells become memory B-cells, others become plasma cells that secrete antibodies
    • Different B-Cells respond to different antigens on a pathogen’s surface
  • 24. Antibodies
  • 25. Antibody Molecules
    • Make up gamma-globulin part of plasma protein (aka immunoglobulins)
    • Each immunoglobulin contains 4 chains of amino-acids
    • Make a “Y” shape, where the legs, or “v”, of the “Y” is the binding site
    • Each binding site is specialized to react to a specific antigen molecule
  • 26. Types of Immunoglobulins
    • G, A, M, E, D
      • E = least common immunoglobulin
    • G, A, M (IgG, IgA, IgM) = most common immunoglobulins
    • IgG – found in tissue and plasma
      • Effective against bacteria, viruses, and toxins
      • Activates complement
    • IgA – found in breast milk, tears, nasal fluid, gastric juice, intestinal juice, bile, and urine
    • IgM – found in the plasma
      • Contains anti-IgA and anti-IgB antibodies
  • 27. Antibody Actions
    • Directly attack antigens
      • Agglunation, precipitation, neutralization
    • Activates enzymes (complements) that attack the antibodies
    • Stimulate local changes to prevent spread of infection (i.e. inflammation)
  • 28. Complements
    • Opsonization – cells more susceptible to phagocytosis
    • Chemotaxis – attracts macrophages and neutrophils
    • Agglutination – clumping together of antigen bearing cells
    • Lysis – causes osmotic rupture of foreign cell
    • Neutralization – altering molecular structure of viruses, making them harmless