Term
two semi-independent parts of the lymphatic system |
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Definition
• Lymphatic vessels • Lymphoid tissues and organ |
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Term
o Lymphatic system functions |
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Definition
• Transport fluids back to the blood • Play essential roles in body defense and resistance to disease |
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Term
What types of pumps propel lymph through the vessels? |
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Definition
NO PUMPS! Skeletal (milking action) and Smooth muscle (rhythmic contraction) propel the lymph through the vessels |
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Term
Name the various types of vessels in lymphatic tissue |
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Definition
Lymph Capillaries
Collecting Vessels |
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Term
Flap-ike minivalves are present in which type of lymph vessels |
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Definition
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Term
How does lymphatic fluid leak into lymph capillaries? |
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Definition
significant gaps and spaces between endothelial cells |
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Term
How are lymph capillaries anchored to connective tissue? |
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Definition
By filaments, which hold and maintain space and position of capillaries in surrounding tissue |
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Term
What causes minivalves in lymphatic cpaillaries to close? |
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Definition
High pressure on the inside closes mini valves. |
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Term
What types of harmful materials enter lymph vessels? |
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Definition
Bacteria, viruses, cancer cells, cell debris |
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Term
Which materials are returned to the blood through the endothelium via lymph? |
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Definition
water, blood cells, proteins |
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Term
Purpose of collecting vessels in lymphatic system? |
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Definition
• Collects lymph from lymph capillaries carries lymph TO and AWAY from lymph nodes
Returns fluid to the circulatory veins near the heart
Right lymphatic duct & Thoracic duct |
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Term
o After exchange in the tissue, then the collecting vessels bring the lymph back to the heart via the....... |
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Definition
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Term
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Definition
Right lymphatic duct & Thoracic duct |
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Term
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Definition
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Term
• Components of the Lymphatic System |
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Definition
o Circulating lymphocytes Lymphatic nodules Lymph nodes |
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Term
Is diffuse lymphatic encapsulated? |
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Definition
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Term
Where is diffuse lymphatic tissue found? |
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Definition
mucosa of the digestive tract, respiratory tree, and genitourinary tract |
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Term
Diffuse lymphatic tissue is located below the epithelium in the..... |
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Definition
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Term
Lymphatic Nodules (lymphatic follicles) |
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Definition
high concentrations of lymphocytes but not surrounded by capsulated |
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Term
Examples of lymphatic nodules are found where? |
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Definition
tonsils, Peyer's patches, appendix |
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Term
what happens to lymphatic nodules when exposed to antigens? |
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Definition
enlargement/ swelling
upon infection, cells undergo rounds of cell division |
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Term
Are lymph nodes encapsulated? |
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Definition
Yes, they are defined by the capsule |
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Term
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Definition
• important filter for lymph (which collects tissues from body fluids) as it makes it's way to blood vascular system
removes it or triggers and immune response
contains macrophages(non specific) in medulla and lymphocytes (specific) in cortex |
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Term
Mucosa-Associated Lymphatic Tissue (MALT) |
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Definition
acts as a sentinel (capture & kill) to protect respiratory & digestive tracts
• Contain T & B cells |
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Term
Which lymphatic components are included in MALT? |
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Definition
Peyer’s patches Tonsils Other small accumulations of lymphoid tissue |
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Term
Where are Peyer's patches found? |
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Definition
wall of the small intestine |
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Term
Purpose of Peyer's patches |
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Definition
o Capture and destroy bacteria in the intestine o Classified as a lymphatic nodule o Concentrations of lymphocytes |
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Term
2 components of lymph nodes |
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Definition
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Term
Medullary component of lymph node |
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Definition
• Inner part • Contains phagocytic macrophages • Stain lighter b/c they contain less lymphocytes |
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Term
Cortex component of lymph node |
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Definition
• Outer part • Contains follicles – collections of lymphocytes |
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Term
Describe Flow of Lymph Through Nodes |
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Definition
Lymph first comes in contact with the capsule, which branches out and continues into the parenchyma via teh trabeculae enters cortex through AFFERENT lymphatic vessel Flows through sinuses inside the node Exits through Efferent |
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Term
Why are there fewer efferent than afferent? |
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Definition
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Term
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Definition
o On the concave surface (Hilum) vessels take the lymph fluid out of the node |
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Term
high endothelial venules (HEV) |
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Definition
• Enable lymphocytes circulating in the blood to directly enter the lymph nodes
have a columnar shape |
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Term
What types of fibers support macrophages and lymphocytes in the medulla? |
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Definition
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Term
Other Lymphoid Organs that contribute to the lymphatic function |
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Definition
o Spleen o Thymus o Tonsils o Peyer’s patches |
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Term
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Definition
destroys worn out blood cells
forms blood cells in the fetus
acts as a blood reservoir |
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Term
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Definition
high concentration of lymphocytes surrounding a branch of the splenic artery
stains very dark because of dense heterochromatin in nuclei |
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Term
Peri-Arietal Lymphatic Sheath (PALS) |
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Definition
the accumulation of lymphocytes investing the central arteries of the spleen and comprising the white pulp |
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Term
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Definition
• filters and degrades erythrocytes
• consists of splenic sinuses and splenic cords |
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Term
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Definition
• consists of splenic sinuses and splenic cords |
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Term
Describe the sinuses of the spleen |
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Definition
cells are NOT tightly attached to neighbor to facilitate old red blood cells to come in |
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Term
Describe the splenic cords |
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Definition
Contain loose connective tissue including macrophages for erythophagocytosis |
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Term
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Definition
Production of mature and immature T-cells
encapsulated
become less effective with age
peak levels only during childhood
Produces hormones (like thymosin) to program lymphocyte production |
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Term
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Definition
established by the thymic lobules
where mature and immature T cells are produced |
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Term
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Definition
T-cells of the thymic cortex |
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Term
Are macrophages present in the thymic medulla? |
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Definition
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Term
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Definition
synthesis of thymic hormones
Tightly packed concentric arrangement of epithelial-like squamous cells
• Hallmark of thymic medulla
includes desmosomes, keratinohyalin granules, hyaline |
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Term
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Definition
trap and remove bacteria and other foreign materials |
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Term
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Definition
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Term
Histological characteristics of tonsils |
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Definition
Crypts, stratified squamous epithelium, lymphatic nodules, and connective tissue. |
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Term
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Definition
o Collection of tonsils monitoring the oral cavity, nasal cavity, and pharynx o Allows exposure of entering pathogens to lymphocytes in the tonsils |
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