Term
| Where are Langerhans cells found? |
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Definition
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Term
| Where are the progenitor cells for B, T, and NK cells found? |
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Definition
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Term
| Where do T-lymphocytes mature? |
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Definition
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Term
| What are epithelial reticular cells? |
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Definition
| These are the cells that are responsible for creating a supporting framework for the maturing T lymphocytes. They are joined together by desmosomes. |
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Term
| Where are immature T lymphocytes found in the thymus? |
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Definition
| They are found densely packed in the cortex |
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Term
| Where are mature T-lymphocytes found? |
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Definition
| They are found in the medulla |
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Term
| What is the purpose of the blood thymus barrier? |
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Definition
| Critical for the process of learning to distingush from self and non-self. |
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Term
| How do mature T lymphocytes exit the thymus? |
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Definition
| Mature T lymphocytes leave the thymus via the post capillary venules. These venules are found in the junction between the cortex and the medulla. |
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Term
| What is nodular lymphoid tissue? What is the difference between primary and secondary? |
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Definition
| It is B lymphocyte rich regions of cells that are clustered as spheroid nodules. Primary nodules are clusters of unstimulated lymphocytes. Secondary nodules develop from Primary nodules after stimulation. |
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Term
| What is a Germinal Center? |
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Definition
| That is the lighter staining portion of a secondary nodule. |
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Term
| What is Diffuse Lymphoid Tissue? |
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Definition
| T lymphocyte rich area with poorly defined boundries that is widely distributed in connective tissues. |
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Term
| What is Mucosa Associated Lymphoid Tissue (MALT)? |
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Definition
| Unencapsulated lymphoid tissue found in the mucosa and submucosa in the GI, respiratory, and genitourinary tracts. Used to protect common sites of microbial invasion where lumens are open to external environment. Gut Associated Lymph Tissue (GALT) is an example. |
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Term
| Where are Peyer's Patches found? |
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Definition
| Peyer's Patches are found in the mucosa/submucosa in the ileum. |
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Term
| Where are palantine tonsils found and what type of epithelium are they comprised of? |
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Definition
| Found in the oral pharynx and are comprised of stratified simple squamous epithelium forming crypts. |
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Term
| Where are the pharyngeal tonsils found and what type of epithelium are they made up of? |
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Definition
| Found in the opening of the respiratory tract and are comprised of ciliated pseudostratifed columnar epithelium forming pleats. |
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Term
| Where are the lingual tonsils found and what type of epithelium are they comprised of? |
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Definition
| Found at the base of the tongue and are comprised of stratified squamous epithelium forming crypts. |
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Term
| What are the functions of the lymph nodes? |
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Definition
1. Filter Lymph 2. Non-specific filtration of microorganisms and particulate matter. 3. Antigen recognition/trapping and immune cell interactions. 4. Activation and proliferation of T and B cells. |
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Term
| Where do afferent lymphatics enter into lymph nodes? |
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Definition
| They enter the node through the capsule and travel into the subscapular sinus. |
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Term
| What is characteristic of the cortex of lymph nodes? |
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Definition
1. Contains diffuse lymphatic tissue rich in T lymphocytes. 2. Contains nodular lymphatic tissue |
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Term
1. What are medullary cords in lymph nodes? 2. What are medullary sinuses? |
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Definition
1. They are branched extensions of dense lymphatic tissue that arise in inner cortex containing B lymphocytes. 2. Dilated spaces continuous with intermediate sinus that separate cords. |
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Term
| What is the order of Lymph Flow? |
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Definition
1. Afferent lymphatics 2. Subscapular sinuses 3. Intermediate sinuses 4. Medullary sinuses 5. Efferent lymphatics |
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Term
| What are the functions of the spleen? |
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Definition
1. Filters blood 2. Immune response 3. Removal of damaged red blood cells 4. Sequesters monocytes 5. Hematopoiesis 6. Storage of blood 7. Recycling of iron |
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Term
| What are the two types of splenic pulp and what are their characteristics? |
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Definition
White Pulp - Organized around PALS, maximize interaction between blood antigens and cells of the immune system Red Pulp - Maximizes interactions between blood and macrophages |
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Term
| Can you describe the splenic blood flow? |
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Definition
1. Splenic Artery 2. Trabecular Artery 3. Central Artery - Branches of the trabecular artery that become ensheathed by T lymphocytes. 4. Penicillar Arteriole - leaving the white pulp, the PALS is lost 5. Sheathed Capillaries 6. Sinusoids |
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