The Immune System & Lymphoid Organs Flashcards

(189 cards)

1
Q

Esta formado por una cápsula de tejido conectivo y algunas celulas de musculo liso las cuales rodean a un grupo de linfocitos

A

Ganglio linfático

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2
Q

Cinco o mas linfocitos con cápsula son

A

Ganglio linfático

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3
Q

La cápsula de tejido conectivo de los ganglios linfáticos producen invaginaciones hacia dentro del ganglio que se llamaran

A

Trabeculas en las cuales se apoyan un sistema de fibras reticulares la cual va a servir de apoyo y estructura a todo el ganglio

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4
Q

Dos capas del ganglio linfático

A

Capa medular central

Y una corteza

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5
Q

Formada por vasos sanguíneos y tejido conectivo que conectaran con el hilio

A

Copa medular del ganglio linfático

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6
Q

Donde se encuentran la mayor parte de nódulos o folículos linfoides en los ganglios linfáticos

A

Corteza del ganglio linfático

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7
Q

Acumulación ovoide dentro del ganglio linfático formada por linfocitos B que forman un acumulos de linfocitos

A

Folículo linfoide o nódulo

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8
Q

Folículo linfoide o nódulo cuando se encuentra activa

A

Palidece su centro (centro germinal) y se compactan formando una semiluna en su porción mas externa menos activa

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9
Q

Funciones de los ganglios linfáticos

A

Filtración de partículas extrañas
Fagocitosis de material que produce reacción antígeno-anticuerpo
Proliferación de linfocitos sensibilizados que se convierten en linfoblastos
Recirculacion de linfocitos maduros

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10
Q

La filtración de partículas extrañas como el carbón se puede ver mas evidentemente en

A

Los ganglios peritraqueales y celulas tumorales

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11
Q

Son la fuente de las células plasmaticas (y de ahí anticuerpos para la respuesta humoral) y de los linfocitos cito tóxicos especificos

A

Linfoblastos

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12
Q

Peso del bazo

A

150 gramos

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13
Q

Órgano de forma discoide que se encuentra en el cuadrante superior izquierdo del abdomen con la presencia de una escotadura en su borde anterior

A

Bazo

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14
Q

El bazo se encuentra encapsulado por

A

Una capa delgada de tejido difícilmente desprendible

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15
Q

Dos estructuras que se pueden diferenciar del bazo

A

Pulpa blanca

Pulpa roja

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16
Q

Estructura del bazo que se encuentra formada por el tejido linfoide en el que predominan linfocitos B y que forman los folículos linfoides.

A

Pulpa blanca

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17
Q

Estructura del bazo que se encuentra formada por los eritrocitos y sus conductos contenidos en el bazo

A

Pulpa roja

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18
Q

Los 4 conductos o estructuras vasculares del bazo

A

Una arteria central delgado que no se anastomosa
Cordones esplacnicos de Billroth
Sinusiodes
Linfocitos T

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19
Q

Son pequeños órganos ovoides intercalados con los vasos linfáticos periféricos y por donde termina pasando toda la linfa

A

Ganglios linfáticos

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20
Q

Son venas grandes de pared delgada que drenan a venas pulpares, estas estructuras vasculares se encuentran rodeadas por linfocitos tipo T

A

Los sinusoides

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21
Q

La distribución de la pulpa roja se hace en zonas, siendo la mas externa

A

La marginal

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22
Q

Capa densa de linfocitos acomodada alrededor de los centros germinales

A

Manto

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23
Q

Función del bazo

A

Hasta el momento del nacimiento mielopoyesis

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24
Q

Interviene en la recirculacion de los linfocitos y en la formación de linfocitos y celulas plasmaticas nuevas que intervienen en la respuesta inmune

A

Pulpa blanca del bazo

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25
Interviene en la limpieza de la sangre al secuestrar, fagocitar, y destruir por medio de macrofagos glóbulos rojos, plaquetas y bacterias y sirve como lugar de almacenamiento de plaquetas
Pulpa roja
26
Destrucción de eritrocitos para que se puedan emplear su hierro en la formación de nuevos eritrocitos
Hemocateresis
27
Órgano irregularmente triangular, impar localizado en el mediastino anterior del tórax encapsulada que se forma de la tercera bolsa branquial
Timo
28
Origen del timo
Tercera bolsa branquial (del endodermo)
29
Alberga linfocitos de origen mesenquimatoso
Timo
30
Superficie irregularmente lobular (generalmente dos lóbulos) de color gris rosado y emcapsulado por una delgada capa de tejido conectivo laxo
Timo
31
Peso del timo al momento del nacimiento
20 gramos
32
En el momento de la pubertad, el timo llega pesar
35 a 50 gramos
33
Esta formado por lobulillos de forma poliedrica, separados por tabiques de tejido conectivo, conformada por una corteza con linfocitos T(llamados timocitos), macrofagos, celulas epiteliales y reticulares
Timo
34
La medula del timo tiende a ser más pálida cuando
Linfocitos T maduros
35
Es donde ocurre la selección positiva o negativa de linfocitos
Unión de la region corticomedular
36
A nivel de la médula del timo se encuentra proliferaciones de celulas epiteliales en forma de hojas de cebolla o rosas llamadas
Corpúsculos de Hassall
37
En el timo es el ecargado de la producción de linfocitos T conocido como
CD4,(helper) y CD8 (citotóxicos) al igual que elimina los linfocitos maduros que van a diferenciarse entre los antígenos propios de los no propios
38
Son ganglios linfáticos ubicados a nivel de la laringe y faringe
Amígdalas
39
Las tres amígdalas más importantes son
Sublingual, palatina y faringea
40
Epitelio de la amígdala faringea
Epitelio columnar pseudostratificado ciliado o epitelio respiratorio
41
Amígalas palatina y sublingual tiene un epitelio
Epitelio plano estratificado no queratenizado
42
La amígdala palatina cuenta con
Invaginaciones de epitelio que forma criptas donde se acumulan dentritus de alimento y celulas descamadas que a simple vista se ve como puntos blancos sobre la amígdala
43
Two partially overlapping lines of defense against invaders and/or other abnormal potentially harmful cells
Innate immunity and adaptive immunity
44
Is none specific, involves a wide mechanism, and is evolutionarily older
Innate immunity
45
Aims at specific microbial invaders, is mediated by lymphocytes and antigen-presenting cells APCs
Adaptive immunity
46
The lymphocytes and APCs for adaptive immunity are distributed throughout the body in
Blood, lymph, epithelial and connective tissues
47
Primary lymphoid organs
Thymus | Bone marrow
48
Secondary lymphoid organs
Lymph nodes Spleen Diffuse lymphoid tissue found in the mucosa
49
The immune cells located diffusely in the digestive, respiratory, or urogenital mucosae collectively known
Mucosa-associated lymphoid tissue MALT
50
Proliferating B lymphocytes in MALT are arranged in small spherical
Lymphoid nodules
51
Physical barrier, part of innate immunity
Skin and mucous membrane located diffusely in the digestive, respiratory, or urogenital that prevent infections
52
Bacteria, fungi, and parasites that manage to penetrate physical barrier are quickly removed by
Neutrophils and other leukocytes in connective tissue
53
Receptors on leukocytes allow the recognition and binding of surface components of such invaders
Toll-like receptors TLR
54
Destroy various unhealthy host cells, including those infected with virus or bacteria as well as certain potentially tumorigenic cells
Natural killer cells
55
In specific regions lower the pH locally to either kill entering microorganisms directly or inhibit their growth
Hydrochloric acid HCl and organic acids
56
Short cationic polypeptide produced by neutrophils and various epithelial cells that kill bacteria by disrupting the cell wall
Defensins
57
An enzyme made by neutrophils and cells of epithelial barrier which hydrolyzes bacterial cell wall
Lysozyme
58
A system of proteins in blood plasma, mucus, and macrophages that react with bacterial surface components to aid removal of bacteria
Complement
59
Paracrine factors from leukocytes and virus-infected cells that signal NK cells to kill such cells and adjacent cells to resist viral infection
Interferons
60
Such bacterias that Avoid phagocytosis by granulocytes and macrophages of innate immunity by covering their cell walls with a capsule of polysaccharides that inhibits recognition and binding to the phagocytes receptors such as
Haemophilus influenzae | Streptococcus pneumonae
61
Is more specific, slower to respond, and An evolutionarily more recent
Adaptive immunity
62
Are aimed at specific microbial invaders and involve production of ... so that a similar response can be mounted very rapidly if that invader ever appears again
memory lymphocytes
63
Immune system communicate with each other primarily vía
Cytokines to coordinate defensive measures
64
A diverse group of peptides and glycoproteins with a paracrine mode of action, such as Chemotaxis, increased mitotic activity in leukocytes, stimulations or supression of lymphocyte activities, stimulate fagocitosis
Cytokines
65
Cytokines induced directed cells movements
Chemotaxis
66
Cytokines have target cells besides immune cells such as
Endothelial cells certain autonomic neurons and cells of endocrine system
67
Cytokines Growth and differentiation factors for leukocytes progenitor cells in bone marrow
GM-CSF, M-CSF
68
Cytokines for Stimulation of inflammation and fever
TNF-alpha, TGF - beta, IL-1
69
Cytokines for stimulation of growth in T lymphocytes and NK cells
IL 12
70
Cytokines for Eosinophils proliferation differentiation and activation
IL-5
71
Cytokines for activation of macrophages
Interferons gamma , IL -4
72
Cytokines for inhibition of macrophages and specific adaptive immune responses
IL-10
73
Chemokines for neutrophils and T lymphocytes
IL 8
74
A molecule that is recognized by cells of the adaptive immune system and elicits a response from these cells, may consistof soluble melecules such as proteins or polysaccharides
Antígens
75
Immune cells recognized and react to small molecular domains of the antígens known as antigenic determinants or
Epitopes
76
The immune response in which lymphocytes are primarily in charge of eliminating the antigen
Cellular
77
Immune response in which antibodies are primarily responsible for the response
Humoral
78
Is a glycoprotein of the immunoglobulins family that interacts specially with an antigenic determinants
Antibody
79
Are secreted by by plasma cells that arise by terminal differentiation of clonaly proliferating B lymphocytes whose receptors recognize and bind specific epitopes
Antibodies
80
Antibodies accumulate in
Blood plasma and intertitial fluid of gland such as mucous, salivary, and mammary glands
81
Immunoglobulins of all antibody molecules have a common design, consisting of
Two identical light chain | Two identical heavy chain bound by disulfide bonds
82
The isolated carboxyl terminal portion of the heavy chain molecules is called the constant
Fc region
83
Fc region are recognized by cell surface receptors on
Basophils and mast cell
84
The first 110 amino acids near the amino-terminal ends of the light and heavy chains vary widely among different antibody molecules called
Variable region
85
The variable portions of one heavy and one light chain Make up anti body's
Antigen-binding site
86
Is the most abundant class representing 75% to 85% of immunoglobulins in blood
IgG
87
Highly soluble, stable and cross the placental barrier into the fetal circulation confering passive immunity against certain infections until the newborn's own adaptive immune system
IgG
88
Is present in almost all exocrine secretions as a dimeric form in which the heavy chains of two monomers are united by a polypeptide called the J chain and secretory component a protein bound released by epithelial cells as undergo trancytosis
IgA
89
Is produced by plasma cells in mucosae of the digestive, respiratory, and reproductive tracts
IgA
90
IgA percentage in the plasma
10% - 15%
91
IgA structure is resistant to proteolysis and reacts with microorganisms in
Milk, saliva, tears, and mucus coating
92
Constitute 5% to 10% of blood immunoglobulin an exits in a pentameric form united by a J chain
IgM
93
First antibody produced in initial immune response, activates complement present in B lymphocyte surface as a monomers
IgM
94
Monomer, with An percentage of 0.002% less abundant in the circulation and exits bound at its Fc region to receptors on the surface of mast cells and Basophils, destroys parasitic worms and participate in allergies
IgE
95
IgE encounters the antigen-antibody complex trigger the liberation of several biologically substances such as
Histamine Heparin And leukotrienes
96
Is the least abundant immunoglobulin in plasma 0.001% , are bound to the surface of B lymphocytes where they act as antigen receptor in triggering B cell activation
IgM
97
Binding of antigen-binding site of an antibody with antigen causes
Neutralization Agglutination Precipitation
98
Antibody covers biologically active portion of microbe or toxins
Neutralization
99
Antibody cross-links cells forming a clump
Agglutination
100
Antibody cross-links circulating particles (toxin) forming an insoluble antigen-antibody complex
Precipitation
101
Three important actions of innate immunity
Complement activation Opsonization NK cells activation
102
Antigen-antibody complexes containing IgG or IgM bind polypeptide of the complement system (a group of 20 proteins produced in the liver) activated by enzymatic reaction , after activation specific complement bind and rupture membranes of invading cells,
Complement activation
103
Ability of receptors on macrophages, neutrophils, and Eosinophils to recognize and bind the Fc portions of antibodies attached to the surface of microorganisms, increases the efficiency of phagocytosis
Opsonization
104
Antibodies bound to antigen on virus infected cells of the body are recognized by NK cells, which are then activated to kill the infected cell by releasing perforins and granzymes
NK cells activation
105
Antigen recognized by lymphocytes are often bound to specialized integral membrane protein complex called
Major histocompatibility complex MHC
106
Proteins of both class of MHC are called..., are encoded by genes in large chromosomal loci having very high degrees of allelic varation
Human leukocytes antigens (HLAs)
107
Are specialized to recognize both class of MHC proteins and antigens they present
T lymphocytes
108
If MHCs on cells of a tissue graft are not similar to those T lymphocytes induce a strong reaction like
Are recognized as markers of potentially tumorigenic, infected or abnormal cell they must eliminate
109
MHC class that proteins bind a wide variety of proteosome-derived peptide fragments representing the range of all proteins synthesized in that cell, all nucleated cells produce and expose self-antigen, which T cells recognize as a signal to ignore those cell
MHC class I
110
Proteins are synthesized and transported to the cell surface but only in cells of the mononuclear phagocyte system, golgi vesicles with MHC complex fuse with endolydomal vesicles containing antigen ingested at the surface of these cells signaling T lymphocytes and activating their responses against sources of these antigen
MHC class II
111
When the donor and the host are the same individual such as a burn patient
Autograft
112
Are those involving identical twins
Isograft
113
Involves two related or unrelated individuals
Homograft
114
Inhibit the action of cytotoxic T cells an immunosupressive drugs
Cyclosporins
115
Most specialized antigen-presenting cells APCs are part of the mononuclear phagocyte system including ..., that have an expression of MHC class II molecules for presenting peptides of exogenous antigens
Macrophages and dendritic cells
116
Both regulate and carry out adaptive immunity
Lymphocytes
117
Approximate percentages of B and T cells in thymus
T 100% | B 0%
118
Approximate percentages of B and T cells in bone marrow
T 10% | B 90%
119
Approximate percentages of B and T cells in spleen
T 45% | B 55%
120
Approximate percentages of B and T cells in lymph node
T 60% | B 40%
121
Approximate percentages of B and T cells in blood
T 70% | B 30%
122
The fibers are produced by fibroblastic
Reticular cells
123
Is usually reticular connective tissue filled with large Numbers of lymphocytes
Lymphoid tissue
124
In all secundary lymphoid tissue the lymphocytes are supported by a rich reticulin fiber network of type
Type III collagen
125
All T lymphocytes have cells receptors, requires costimulation by the
TCR and either CD4 or CD8
126
Are long-lived lymphocytes and constitute 75% of the circulating lymphocytes
T lymphocytes
127
T lymphocytes recognize antigenic epitopes vía surface protein complex termed
T cell receptors TCRs with two glycoproteins alpha and beta chain
128
Are characterized by CD4, the coreceptor with the TCR for binding MHC class II molecules and the peptide it present, activated by such binding, helper T cells assist immune responses by producing cytokines that promote differentiation of B cells into the plasma cells, activate cytotoxic T lymphocytes and induce many parts of An inflammatory reactions
Helper T cells
129
Are CD8, together with TCRs bind specific antigens on foreign cells or virus infected cells displayed by MHC class I molecules also result sin the population of memory cytotoxic T cells
Cytotoxic T lymphocytes
130
In the presence of....., from helper T cells, cytotoxic T cells that have recognize such antigens are activated and proliferate
Interleukin 2
131
Are CD4 CD25 and serve to inhibit specific immune responses, also identified by the presence of Foxp3 transcriptor factor
Regulatory T cells
132
transcriptor factor crucial in allowing immune tolerance, mantaining unresponsiveness to self antigens and supressing excessive immune responses.
Foxp3
133
Smaller subpopulation whose TCR contains gamma and delta chains , migrate to the epidermis and mucosal epithelia becoming largely intraepitelial and dont circulate in secundary lymphoid organs
Gamma- delta lymphocytes
134
The retrovirus that produces...., infects and rapidly kills helper T cells, reduction of this lymphocytes group cripples the patient's immune system rendering them susceptible to opportunistic bacterial, fungal, etc.
AIDS aquired immunodeficiency syndrome
135
The surface receptors for antigens are monomers of IgM or IgD covered by about 150,000 such B cell receptors (BCR)
B lymphocytes
136
BCR bind An antigen which may be free in solution, on An exposed part of An infectious agent, or already bound to antibodies and undergo
Endocytosis
137
Degraded antigen in endosomes , peptides from the antigens are present on
MHC class II
138
In all secundary lymphoid tissue B lymphocytes interact with
Follicular dendritic cells FDCs which have long filamentous processes are mesenchymal in origin
139
Surface of follicular dendritic cells are covered with antibody-antigen complexes bound receptors for complement proteins and for immunoglobulin Fc regions causing B cells to attach and become activated and aggregate as a small
Primary lymphoid nodule or follicle
140
With the help of adjacent Th cells, B cells form a much longer
Secondary lymphoid nodule
141
Secondary nodules are characterized by a lightly stained ..... Filled with large Lymphoblast or centroblast undergoing immunoglobulin gene recombination, rapid proliferation and quality control
Germinal center
142
Growth of activated B cells in germinal centers is exuberate and very rapid, causing noroliferating B cells to be pushed aside and produce
Mantle
143
After ..... Weeks the germinal center and Mantle are dispersed
2 or 3 weeks
144
Specific B lymphocytes differentiate into
Plasma cells secreting antibodies are said to provide humoral immunity
145
Main function of thymus
Induction of central tolerance, which along regulatory T cells preventa autoimmunity
146
Failure of the third (and fourth) pharyngeal pounches to develop normally in the embryo leads to
DiGeorge syndrome cause by thymic hypoplasia
147
Each lobule has An outer darkly Basophilic
Cortex
148
Cortex surround a more lightly stained
Medulla
149
Three major types of thymic epithelial cells TECs
Blood thymus barrier Cytorericulum Corticomedullary barrier
150
Squamous TECs form a layer joined by desmosomes and occluding junctions, line the connective tissue of the capsule and septa and surround the microvasculature, together with the vascular endothelial cells and pericytes forms
Blood thymus barrier
151
TECs with processes containing keratin tonofilaments joined by desmosomes form a....., to which macrophages and lymphocytes attach instead of the reticulin fibers, express MHC both proteins, these cells are APCs
Cytoreticulum
152
TECs that express MHC class II molecules but form a structure contribute in a barrier between the regions of each lobule
Corticomedullary barrier
153
Three types of medullary TECs
A second layer of the boundary between cortex and medulla A Cytoreticulum Hassall corpuscles
154
Up to 100 micrometers in diameter, secret cytokines that control activity of local dendritic cells, that promote development of regulatory T cells for peripheral tolerance
Hassall corpuscles
155
The selection process for each pre T lymphocytes begin sin the cortex, ends in the medulla and last about
2 weeks
156
Survival dependent on ability to bind to MHC molecule take place in the cortex in thymus
Positive selection
157
Percentage of cells that undergo apoptosis because they dont bind to MHC molecule in positive selection
80%
158
Occurs in medulla , survival dependent on not recognizing self antigen because medullary thymic epithelial cells express high level of Aire
Negative selection
159
Percentage of cells survive selection Process in the thymus
2%
160
Is one of the largest lymphoid organs containing up to 70% of all the body's immune cells
MALT
161
Most lymphocytes in MALT are
B cells
162
Located posteriorly on the soft palade covered by stratified Squamous epithelium, the surface area is enlarged with 10 to 20 deep invagination or tonsillar crypt, is underlain by dense connective tissue that acts as partial capsule.
Palatine tonsils
163
Situated along the base of the tongue covered by stratified squamous epithelium with cripts with lack distinct capsules
Lingual tonsils
164
Situated in the posterior wall of nasopharynx covered by pseudostratified ciliated columnar epithelium with s thin underlain capsule, the mucosa is invaginated with shallow infolding but Lacks crypt
Pharyngeal tonsil
165
Inflammation of tonsils, more common in children than adult
Tonsillitis
166
Hyperplasia and enlargement of the tonsils to form
Adenoids
167
Large aggregates of lymphoid nodules that contains dozens of nodules with no underlying connective tissue, located in ileum
Peyer patches
168
The simple columnar epithelium that cover nodules of Peyer patches include large epithelial
M cells
169
On the basal side M cells have
Large intracellular pockets with lymphocytes and dendritic cells and open to the underlying lymphoid tissue through a highly porous basement membrane
170
A short, small diameter projection from the cecum, completely filled with lymphoid tissue, the lumen contains the normal flora of the large intestine and serve to retained beneficial bacteria ther during diarrheal ilnesses
Appendix
171
Total present in the human body
400 - 450 lymph nodes
172
Are bean shaped, encapsulated structures generally only 10 mm by 2.5 cm size
Lymph nodes
173
Lymph nodes are more abundant in
Axillae (armpits) and groin, along the vessels of the neck, thorax, abdomen specially in mesenteries
174
Valves in the lymphatic ensure the flow is
Unidorectional
175
Three major regions of lymph nodes
Cortex Medulla Paracortex
176
Cortex of lymph nodes includes
Subcapsular sinus | Lymphoid nodules
177
Part of the lymph nodes Cortex immediately inside the capsule, receives lymph from afferent lymphatic. From this space cortical sinuses branch internally among the lymphoid nodules
Subcapsular sinus
178
Part of the lymph nodes Cortex with or without germinal centers, fill most cortical áreas, formed largely by helper T lymphocytes and proliferating B Lymphoblast
Lymphoid nodules
179
Region between the cortex and medulla does not have precise boundaries but can be distinguish from outer Cortex by its lack of B cells lymphoid nodules but contains T cells
Paracortex
180
Specialized postcapillary venules in the paracortex , that represents An important entry point for most (90%) lymphocytes into lymph nodes, called
High endothelial venules HEVs
181
Part of the lymph nodes medulla
Medullary cords | Medullary sinuses
182
Part of the lymph nodes medulla are branched cordlike masses of lymphoid tissue extending from the paracortex that contain B and T lymphocytes and many plasma cells
Medullary cords
183
Part of the lymph nodes medulla dilated spaces line by discontinuous endothelium that separate the medullary cords, are continuous with the cortical sinuses and converge at the hilium as the efferent lymphatic vessels
Medullary sinuses
184
Neoplastic proliferation of lymphocytes producing a malignant
Lymphoma
185
The largest single accumulation of lymphoid tissue in the body and the main site of old erythrocytes destruction
Spleen
186
Percentage of white pulp of the spleen
20%
187
Consist primarily of T cells with some macrophages ,DCs, and plasma cells as part of white pulp.
PALS
188
Surround by PALS these vessels ar known as
Central arterioles
189
Each central arteriol leaves the white pulp and enter the red pulp, losing its sheath of lymphocytes and branching as
Penicillar arterioles