Lymph system Flashcards
What are the two semi-independant parts of the lymphatic system
Lymphatic Vessels
various lymphoid tisssues & organs
What kind of pressures move fluid from the capillary beds
Hydrostatic and Osmotic
What is it called when there is fluid buildup
Edema
What are lymph vessels lined with
Endothelial cells, thin layer of smooth muscles and adventitia (outermost connective tissue covering of an organ,vessel or other structure)
How does fluid enter the lymph vessels
Gaps in the side that open one way. Can come in but can’t leave through those openings.
True or False: Bacteria and viruses can enter blood capillaries, not lymph vessels
False
Where is the lymph returned to the blood and which side drains what
Right lymph duct drains right head and chest.
Left (large duct) drains the rest of the body
Front limb drains into axillary, Pelvic into iliosacral lymph center
Drains into the subclavian.
Name the 3 ways lymph is moved
Skeletal pumping (moving, walking), breathing, and smooth muscles.
What makes up 40% of the equine lymphatic system
Elastin
Is there lymph fluid in the hoof and lower leg with the lack of muscle there
Yes
What is the hoof pump
Hoof pump fills and empties the lymphatic vessels through contact with the ground and suspension of the moving foot
Where does the lymph from the hoof and leg drain
The deep collector system/ deep collector vessels
Where does lymph travel
Towards the heart
What is located in the lymph system cleaning the fluid
Macrophages and Lymphocytes
Where do the lymphocytes come from
Red bone marrow
Explain lymph traveling through a node
The lymph enters the convex side of the node through the afferent vessels and leaves through the hilus vs efferent vessels. There are move afferent vessels then efferent so the lymph leaving takes longer so that it can being fully cleaned.
Name 5 lymphoid organs
Tonsils- first line of defense from air borne pathogen. 3 types are palatine, pharyngeal and lingual
Thymus- primary lymphatic organ. Where t-cells mature
Spleen-cleans and destroys red blood cells as well is a blood resevoir
Peyers Patch- located in small intestine. Primary lymphatic tissue. In where most waste & bacteria can manifest
Bone marrow- location of lymphocyte production & B-cell maturation
Name the epithieum cells on the Palatine , Pharayngeal & Lingual Tonsils
Stratified squamous, pseudostratified ciliated columnar epithilium & stratified squamous epithilium.
What is the primary lymphatic organ
Thymus
What is different about the spleen
Filters blood, destroys worn out blood cells, stores platelets and acts as a blood resevoir
Where is the spleen located
Left side of body
Where is the peyers patch located
Small intestine
What does MALT and GALT stand for
mucosal-associated and gut-associated lymphoid tissue
What is the primary lymphoid tissue
Peyers Patch
Differentiate lymphocytes and where they mature.
T-lymphocites and B-lymphocites.
Both come from bone marrow but T-cells mature in thymus and B-cells mature in Bone marrow
What is the function of the lymphatic vessels
Picks up fluid and proteins that are leaked from the blood into interstitial space
How do lymphatic capillaries and blood capillaries differ structurally from each other
Lymphatic capillaries are blind ended and not fed by arteries like blood capillaries are. Lymphatic have minivalves that make them more permeable than blood capillaries.
What is the benefit of having fewer efferent than afferent lymphatic vessels.
slows down the lymph in the node almost to a stop, giving time to macrophages and lymphocytes to more closely monitor the lymph.
In which three regions of the body are the lymph nodes most dense
axillary, inguinal and cervical
How do innate and adaptive defenses differ
innate is always ready to protect and is non-specific (skin, mucous, phagocytes, inflammatory response…). adaptive is specific to the antigen (Lymphocytes, antibodies, antigen presenting cells)
What are 4 common indicators of inflammation
Heat, redness, pain, swelling
Explain the inflammatory response
When cells are injured, they release chemicals called histimine and kinins that cause blood vessels to become leaky, activate pain and attract phagocytes and wbc to area (chemotaxis). Dialation of blood vessels increase blood to area (causing redness and heat). Increased permeablility of capillaries allows plasma to leak out into the tissue (edema). Neutrophils are attracted to the area from the bone marrow to start clean-up (weak phagocyte), monocytes follow neutrophils and within 8-12 hours become insatiable phagocytes.
Explain what a B-cell does
B cell meets an antigen that binds to its receptors. This activates the B cell (sometimes it requires Helper T cell for direction). It then goes on to grow and multiply making plasma cells. Most plasma cells will produce antibodies where a few will become memory cells to remember the antigen in future meetings.
Name 7 Nonspecific body defense
Surface membrane barriers, Phagocytes, Natural Killer Cells, Inflammatory Response, complement, interferons, fever.
What is the difference between NKC, complements and interferons
NKC recognizes certain sugars and attack by releasing perforins that target the cells membrane and nucleus disintegrating them.
Complements are a group of 20 proteins that attach to the antigen, shoot membrane attack complexes that make lesions into the cell which allows water to rush in and explode the cell.
Interferons are virus infected cells that release proteins that bind to nearby cells that interfere with the virus’s ability to multiply.
How does a fever help the body
During a fever, the liver an spleen gather up zinc and iron to make them less available to bacteria. It also increases the metabolic rate of tissue cells which speeds up repair process.
What are the different T-cells
Helper T Cells, Cytotoxic T cells (killer t cells), and regulatory/supressor t cells.
What is the role of the helper T cell
Prods b and t cell into more rapid division, attracts wbc such as neutrophils.
What is MADGE
Immunoglobulin classification
Which Immunoglobulin is most abundant and can cross the placenta
IgG
Which immunoglobulin is a pentamer
IgM
Which immunoglobulin is found in saliva, tears, intestinal juice and milk
IgA (dimer)
Which immunoglobulin is always attached to b cells
IgD
What is the double handshake with the T cell
T cell has to attach to a self-protein and the antigen before it’s activated
How is the lethal hit from a T cell done
The T cell releases perforin which creates holes in the antigens membrane, then granzymes come in and kill the antigen.
Where does the lymph flow towards
The heart
Where in the Lymph node is the bacteria yompchuewalized (destroyed by macrophages)
in the medulla sinus
