Term
| General function of Epithelium |
|
Definition
absorption, secretion, protection
*cell junctions |
|
|
Term
| Specialized epithelial functions |
|
Definition
Transport molecules across epi.
Prevent transport of materials across epi.
Sensory (taste buds, retina) |
|
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Term
| Two parts of complete basement membrane |
|
Definition
Basal lamina
Reticular lamina |
|
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Term
|
Definition
Zonula occludis
Zonula adherense
Macula adherons
Gap junctions |
|
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Term
|
Definition
tight junction or occluding junction
attaches and seals the intercellular space
seen at the top of the junctional complex
Cell membranes of 2 cells share intrinsic membrane proteins
Function:
1. strong attachment
2. prevention of passage of materials between cells |
|
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Term
|
Definition
adhesion belt
cytoskeletal attachment for structural support
poor cell to cell attachments for maintaining cell structure |
|
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Term
|
Definition
Spot welds
provide strong attachment between cells through protein plaque, tonofilaments, and transmembrane proteins |
|
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Term
| Basic characteristics of epithelium |
|
Definition
Cells are adjacent to each other
Have a complete or partial basement membrane
Avascular-obtain nutrition by diffusion
Associated with vascular connective tissue
Cells held together by cell junctions |
|
|
Term
| Partial basement membrane |
|
Definition
basal lamina only
provides decreased diffusion distance, maximizing potential diffusion |
|
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Term
|
Definition
permanent of 6 connexons from adjacent cells forming a macromolecular passageway between cells
lumen can be opened and closed for isolation of material to abnormal cells
Functions:
1. strong attachment
2. exchange of materials between cells (ex: nutrients among osteocytes, ions among cardiac myocytes)—“innate in action”
[other, more specialized junctions, include: hemidesmosomes, fascia occludens, fascia adherens] |
|
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Term
| Hemidesmosomes and focal point contacts |
|
Definition
| junctions that hole the epithelium to the basement membrane and the ct below. |
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Term
|
Definition
|
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Term
|
Definition
Single layer of flattened cells
Ex. location: lung, parietal layer of the Bowman's capsule in the kidney, serosa on the outside of organs
Functions: barrier, filter |
|
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Term
|
Definition
Single layer of cube shaped cells, nucleus occupies much of the cell cytoplasme, looks like a square
Locations: exocrine ducts, thyroid follicular cells, kidney tubules
Functions: absorption, secretion
polarised |
|
|
Term
|
Definition
Single layer of cells that have height; more cytoplasm than simple cuboidal, rectangular, polarized
Locations: stomach, small intestines, gall bladder, larger exocrine ducts
Functions: absorbtion, secretion |
|
|
Term
| Ciliated Pseudostratified Epithelium |
|
Definition
Respiratory Epithelium
Three cell types:
sustentacular cells
Goblet cells
Basal cells
Location: trachea, respiratory region of nasal cavity, bronchi |
|
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Term
|
Definition
Type of Ciliated Psuedostratified Epithelium
Columnar cells that contain cilia anchored in the apex of the cell by basal bodies
Function: produce mucus |
|
|
Term
|
Definition
Modified columnar cell
Function:Produce and secrete mucus
polarized |
|
|
Term
|
Definition
Short pyramidal shaped cell that does not reach the surface
Function: act as a stem cell for goblet and sustentacular cells |
|
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Term
|
Definition
AKA brush border or Stratified border
Finger-like projections at the apical of some epithelial cells
Function: increase surface area, increase absorption
Location: kidney tubule cells, small intestines |
|
|
Term
|
Definition
extremely long microvilli
less numerous
Not related to true cilia
Function: increase surface area
Location: epididymis, cochlear hair cells |
|
|
Term
|
Definition
thin apical hair like extension of the cytoskeleton
Function: to move something over a surface
Location: trachea, fallopian tube |
|
|
Term
|
Definition
Cannot absorb or secrete, basal bodies block the surface
Have lots of mitochondria |
|
|
Term
|
Definition
Surface layer of glycoproteins and carbohydrates
Produced by: epithelial cells
Function: cell recognition, protection, other
Location: stomach and small intestines |
|
|
Term
|
Definition
Two or more cell layers thick
Named for shape of superficial cells
Protective |
|
|
Term
|
Definition
Multiple layers of cells that flatten out from basal layers to superficial layers.
Superficial cells are alive
Function:Protection from abrasion
Location: esophagus, tongue, oral cavity
Problems: no protection from drying, limited thickness |
|
|
Term
| Keratinized Stratified Squamous |
|
Definition
Multiple layers of cell flattening out from basal to superficial layer. Superficial layer covered by nonliving layer of keratin
Function: protection in dry
Location: skin |
|
|
Term
| Layers in epithelium of skin |
|
Definition
Stratum basale
Stratum Spinosum
Stratum Granulosum
Stratum Lucidium
Stratum Corneum |
|
|
Term
|
Definition
AKA stratum germinativum
1-2 layers of keratinocytes. Mitotic and closest to the dermis
Living |
|
|
Term
|
Definition
| Multiple layers of "spiny shaped" keratinocytes that produce lipids and keratohyalin vacuoles. Thickness can vary |
|
|
Term
|
Definition
| uppermost 1-2 layers of flattened living keratinocytes that contain flattened, condensed keratohyalin vacuoles |
|
|
Term
|
Definition
thin layer of dead/dying keratinocytes.
Only present in thick skin |
|
|
Term
|
Definition
Made of dead cells, keratin, and lipids
Thickness varies
Functions: prevent water loss
Protect from abrasion
Barrier against microorganisms |
|
|
Term
| Epidermal pegs and dermal papillae |
|
Definition
| strengthen epithelium by increasing surface area of attachment to connective tissue |
|
|
Term
|
Definition
|
|
Term
|
Definition
Found in Stratum Basale
Protect against UV
Pigment melanin is produced in melanozomes, pinched off and taken in by keratinocytes |
|
|
Term
| Factors determining skin color |
|
Definition
Size of melanosomes
Number of melanosomes
Placement of melanin in keratinocytes |
|
|
Term
|
Definition
Recognize external foreign antigens
Found in stratum spinosum and stratified squamous epithelium
Food alergies |
|
|
Term
|
Definition
Provide touch receptors
Found in stratum basale
Associated with free nerve endings, respond to compression |
|
|
Term
|
Definition
Increases melanocyte numbers,
Decreases Langerhans cells |
|
|
Term
|
Definition
Two layers of cells. Flattened basal layer, cuboid superficial layer
Add protection and structure to ducts
Locations: larger ducts in sweat glands and salivary glands |
|
|
Term
|
Definition
Two layers of cells.
Basal layer is cuboidal, suferficial columnar.
Very rare
Add protection and structure
Provide a transition between epithelial types
Location: large ducts in pancreas, parts of male urethra, conjunctiva of eye |
|
|
Term
|
Definition
Urinary cells
Multiple layers
protection, stretch
Location: most of urinary tract |
|
|
Term
| Transitional (urinary) specializations |
|
Definition
Thin and Fenestrated (holey) basement membrane (need strong attachments)
Large rounded superficial cells
Well developed Zona Occludens (prevent urine from seeping between cells)
Many are binucleated
Get more O2 because stretch allows for thinner membrane and fenestrated basal membrane |
|
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Term
|
Definition
| Product is released into a duct or onto epithelial surface |
|
|
Term
|
Definition
Cells concerned with the primary function of an organ
ex. biceps-skeletal muscle cells |
|
|
Term
|
Definition
components providing mechanical and metabolic support
Ex. biceps: blood vessels, nerves, connective tissue |
|
|
Term
| Three methods of subclassifying exocrine secretion |
|
Definition
Morphology
Method of Secretions
Product Secreted |
|
|
Term
|
Definition
Shape and duct arrangement
Secretory units: Tubular Vs. Acinar (alveolar)
Duct Arrangement: Unbranched vs. Branched
Ex. Compound branched tubular gland |
|
|
Term
|
Definition
eccrine
Most common form of secretion, by exocytosis.
No cell damage, no cytoplasm is released, no odor
Ex. Goblet cell, salivary glands, pancreas, all sweat glands in children |
|
|
Term
|
Definition
Cell matures and dies
Secretory product is vacuole, cytoplasm, and other cell contents
Odor
Ex. Sebaceous glands (hair), tarsal (meibomain) glands of eyelid |
|
|
Term
|
Definition
Minimal cell damage-cell repairs and continues living
Secretory product is vacuole, some cytoplasm, etc.
odor
Ex. lactating mammary glands, some adult sweat glands, ceruminous glands in external auditory canal, ciliary (Moll's) gland in eyelid |
|
|
Term
|
Definition
| Smallest division of a gland, group of cells surrounding a cavity |
|
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Term
|
Definition
| a small group of serous cells attached to a mucus acinus |
|
|
Term
|
Definition
Contractile
Wrap around the acini is some exocrine glands
Force product from cells
Location: Sallivary glands, sweat glands, Lacrimal glands (tear production), Lactating mammary glands |
|
|
Term
|
Definition
Produce: proteins (in general), usually enzymes
Shape: Cuboid to columnar (trapezoid)
Nucleus: Round and noticeable
Stain: Yep, varies in darkness
Ex. Pancreas, Parotid gland, Chief cells in stomach |
|
|
Term
|
Definition
Produce: lipid/carb material compound
Nucleus: flat and on side
Stain: Lightly
Ex. Goblet cells, mucus cells in stomach, minor salivary glands in tongue and palate |
|
|
Term
|
Definition
Produce: Serous and Mucus
serous demilunes – attached to mucus units; secrete into main duct via canaliculi between mucus cells
Ex. Sublingual and submandibular salivary glands |
|
|
Term
|
Definition
| Myoepithelial cells: contractile elements, ANS fibers to each cell
Hormones
Blood supply: |
|
|
Term
|
Definition
Product released into nearby ct, vascular distribution to specific organ
Product=Hormone |
|
|
Term
| Subtypes of Endocrine secretions |
|
Definition
Paracrine Secretion: Signaling cell is close to target cell, no blood flow needed
Autocrine secretion: signaling cell is its own target |
|
|
Term
| Regulation of Endocrine Secretion |
|
Definition
Hormones, Positive Negative feedback loops
ANS |
|
|
Term
|
Definition
patchy skin lesions
Accelerated keratinocyte life cycle-1 week
Cells accumulate in stratum corneum
Inflamation is in dermal papillae
Cyclic and etiology is unknown |
|
|
Term
|
Definition
Spots with extra pigment
Increase in melanin without Increase in melanocytes
Fade in winter, darken in summer |
|
|
Term
|
Definition
patches with no color, no melanocytes
Unkown cause, associated with systemic diseases: hypo/hyperthyroidism, diabetes, Addison's disease, pernicious anemia, leprocy |
|
|
Term
|
Definition
naevi
Discoloration due to a proliferation of melanocytes |
|
|
Term
|
Definition
Melanocytes become mitotically active and invade dermis
Very invasive and metastatic
Treatment:surgery and chemo |
|
|
Term
|
Definition
Matrix composed of ground and fiber tissue
Consists mostly of intercellular components, limited number of cells |
|
|
Term
|
Definition
Provide structural support: cartilage, bone, capsules
Provide a medium for exchange of materials
Defense and protection
Storage of fat (energy source) |
|
|
Term
|
Definition
Derived from mesenchyme
Support cells seperated by matrix
Support cells make the matrix
Cells adhere to matrix instead of other cells |
|
|
Term
|
Definition
| made of ground substance and fibers |
|
|
Term
|
Definition
Glycosaminoglycans contribute to ground substance
Have Covalent bonding sites so will bond with other GAG's and proteins
No affinity for water
molecules will not support inflamation
Ex. keratin sulfate, chondroitin sulfate, heparin sulfate, dermatin sulfate |
|
|
Term
|
Definition
Do not bond with other GAG's readily
Have an affinity for water-weak electrostatic bond
Ex. Hyaluronic acid |
|
|
Term
| Tissue with high HA concentration |
|
Definition
Has higher H2O content
Water content can change
support inflamation |
|
|
Term
| Positive aspects of inflamation |
|
Definition
Increase fluidity so defense cells can move about
Increase the number of effective cells |
|
|
Term
| Negative aspects of inflamation |
|
Definition
Swelling can damage blood vessels (edema)
damage nerves and cells (too much pressure) |
|
|
Term
|
Definition
| excessive fluid remaining in the interstitial spaces |
|
|
Term
|
Definition
At least 20 types
Most common CT protein
Type I makes 90%
Complex, coded for on many genes |
|
|
Term
|
Definition
90% of body collagen
Known for its tensile strength, but unable to stretch |
|
|
Term
|
Definition
Fiber production slows
More mistakes in making collogen I |
|
|
Term
|
Definition
| necessary for the propper cross-linking within collagen I fiber Scurvy is the result of deficiency |
|
|
Term
|
Definition
Composed of elastin and microfibrils
Stretch 150% of its resting length
Important in blood vessels and lungs
Produced by fibroblasts in CT
Produced by smooth muscle in blood cessels
Simpler than Collagen I, fewer pathologies associated |
|
|
Term
|
Definition
| As age increases amount of fibers decreases. Surprised? |
|
|
Term
|
Definition
| Defective fibrillin (a microfibrie) related to elastic fibers |
|
|
Term
|
Definition
Collagen III
Simple, easy to produce
Lasts 3 days
No serious pathologies
1st fiber produced during healing |
|
|
Term
|
Definition
|
|
Term
|
Definition
Most important cell in ordinary CT
Derived from mesenchyme cells
Mostly a fixed cell
Occasionaly divides
May change into other cell types under special conditions |
|
|
Term
| Structural Fibroblast cell |
|
Definition
Produce and maintain matrix
Function in healing
Scar formation due to fibroblast activity |
|
|
Term
|
Definition
Considered to be dense irregular connective tissue
Mature scars are almost avascular and contain only mature fibroblasts=fibrocytes
70% as strong as original tissue |
|
|
Term
|
Definition
mature less active fibroblasts.
long lived with low energy requirements
Structural, limited capabilities
Can: maintain matrix-produce HA, Ground substance, Reticular fibers
Cannot: produce Collagen I and elastic fibers |
|
|
Term
|
Definition
Produce cytokines and enzymes *collagenase and elastase
Can phagocytize |
|
|
Term
|
Definition
Possess features of fibroblasts and smooth muscle cells
Functions:
Wound closure
Tooth eruption |
|
|
Term
|
Definition
Do not divide or change into other cell types
Derived from mesenchyme cells
Function in lipid storage (energy source, cushioning, insulation) |
|
|
Term
|
Definition
Do not divide
Short lived (2-3 weeks)
Derived from B lymphocytes
Large cells
"clock faced" nucleus
Function: produce immunoglobins (antibodies) |
|
|
Term
|
Definition
Histiocytes
Reniform nucleus
can divide
Derived from monocytes
Very important defensive cell
Part of the Mononuclear Phagocyte System |
|
|
Term
|
Definition
Mononuclear Phagocyte System (Reticuloendothelial System)
Each member:s
Arises from common ancestor in bone marrow
able to phagocytise
can display particular receptors |
|
|
Term
|
Definition
|
|
Term
|
Definition
Phagocytosis: foreign debree, microorganisms
Antigen Presenting Cell (APC): Present info to T helper cells, Probably a seperate macrophage population
Create foreign body giant cells:fusion of 30-40 macrophages, response to a sizable object or pathogens (TB, Leprocy)
Release cytokines and other products:
by enzymes (coagenase, elastinase) and interlukens |
|
|
Term
|
Definition
Large defensive cells
Contain cytoplasmic granules
Found in CT proper
Ocasionally divide
Lifespan:days to months
Derived from a precursor cell from bone marrow (once thought to be from basophils). |
|
|
Term
|
Definition
Mediate:
inflamation
Simple Allergy
Anaphylaxis
Most types of asthma
Release Primary Mediators in cytoplasm granules
Histamine, Heparin, ECF, and NCF
Produce and release secondary mediators |
|
|
Term
|
Definition
"on switch"
Increase permiability of capilaries and venules
Vasodilation of arteerioles and small arteries
Cause contraction of viscera/smooth muscle, especially in gut and lungs(initiates asthma) |
|
|
Term
|
Definition
Chondroitin sulfate
"off switch"
Binds to and inactivates histamine (after a lag delay) |
|
|
Term
|
Definition
Eosinophil Chemotactic Factor
Attracts eosinophils |
|
|
Term
|
Definition
Inhibit leukotrienes
Produce a factorr that inhibits mast cell degranulation
Phagocytize IgE-allergin complexes and mast cell granules
Limit the effects of histamine and leukotrienes
Also try to kill parasytic worm larvae |
|
|
Term
|
Definition
Neutrophil Chemotactic Factor
Primary mediator
Attracts Neutrophils |
|
|
Term
|
Definition
Same effects as histamine, but more potent
Main problem in asthma attacks-brachiospasms |
|
|
Term
| Stimuli Activating Mast Cells |
|
Definition
Direct mast cell trauma
Phagocytosis
IgE-allergin complex |
|
|
Term
|
Definition
Primary Immune Response
Elicits IgE formation which binds to mast cells
Mast cells become sensitized (ready to react to exposure)
Some release of granules and producrs, but usually weak |
|
|
Term
| Second exposure to same antigen: |
|
Definition
Allergin binds to "sensitized" mast cells and mast cells degranulate
Immediate degranulation and leukotriene production
Quick full blown response |
|
|
Term
| Basic Inflamatory reactions |
|
Definition
1. Stimulus:Phagocytosis ex. response to dead cells, damaged fibers and debris
2. Mast cells degranulate: localyzed rxn
3. Histamine reacts first: increase permiability and dilate arterioles
4. Leukotrienes take effect: (SRS-A) Slow reacting affect to anaphalactics. Extend the affects of histamine (1000X more powerful than histamine)
5. Heparin and ECF react last (lag time)
Heparin counteracts histamine=return to normal
ECF attracts eosinophils to limit the reaction |
|
|
Term
| Immediate Hypersensitivity Response |
|
Definition
Simple allergy
Stimulus: IgE/allergen complex
Example: hay fever and contact dermatitis
Mast cells degranulate and produce various substances
Localized inflammatory response at sight of allergin contact |
|
|
Term
|
Definition
In the nose:CT below epi
Leaky caps and venules-CT swells-Stuffy nose
Dilation of arterioles=
+blood,O2, Seromucus secretion
Runny nose |
|
|
Term
|
Definition
In skin-dermis below epi
Leaky caps and venules-excess fluid in dermis:CT swells-hives and weepy skin
and
dilation of arterioles-increase blood
redish tint to skin due to excess bloodflow in the dermis |
|
|
Term
|
Definition
Stimulus: IgE/allergen complex in the blood (Bee venom, peanut oil, seafood, penicillin)
Systemic mast cell and basophil degranulation and secretion
Systemic inflamatory response
Anaphylactic Shock=cardiovascular collapse and circulatory shock
Caused by excessive blood loss |
|
|
Term
|
Definition
(mouth breathing cold dry air)
allergens in the air
childhood onset |
|
|
Term
|
Definition
Allergy is unknown
Develops in adults, often <40 years
Follows lower respiratory illness |
|
|
Term
|
Definition
IgE/allergen complex
or
Secondary factors like fatigue, stress, endo changes, emotions, air temperature, foods, asprins |
|
|
Term
|
Definition
Primary: release of leukotrienes- strong and prolonged smooth muscle contraction in the bronchioles
Secondary: Inflamation in lungs-fluid buildup due to leaky cap and venules-decreased O2 and CO2 exchange |
|
|
Term
|
Definition
Monocytes
neutrophils
Eosinophils
Basophils
Lymphocytes |
|
|
Term
|
Definition
|
|
Term
|
Definition
Phagocitize bacteria
Attracted to accute inflamation sites due to NCF |
|
|
Term
|
Definition
Combat parasitic worms
attracted to allergic inflamation |
|
|
Term
|
Definition
Similar to mast cells
initiate maintain and control inflamation (in CT) |
|
|
Term
|
Definition
Usually not many in CT unless you have chronic inflammation.
Function in humoral and cell mediated immunity |
|
|
Term
|
Definition
Change into another cell type
Can divide
Exist in adults, but decrease with age
Cells have sparse pale staining cytoplasm with an oval nucleus |
|
|
Term
|
Definition
Make more permanent reticular fibers
Fiberblast produce reticular fiber when needed on a temp. basis (wound healing) |
|
|
Term
| Loose Connective Tissue Characteristics |
|
Definition
Larger # of cells, many cell types
Fewer Fibers
Higher ground substances
Quite vascular |
|
|
Term
| Types of loose connective tissue |
|
Definition
Loose Areolar
Loose irregular |
|
|
Term
|
Definition
Greater and lesse omentum
"Filler" CT for in small spaces |
|
|
Term
|
Definition
in Dermis of skin (papillary layer)
Under epithelium in organs(stomach GI) |
|
|
Term
| Dense Connective Tissue Characteristics |
|
Definition
Fewer # of cells and cell types
Many fibers
Lesser ground substance
Less vascular (except for Reticular layer of dermis) |
|
|
Term
|
Definition
Dense Irregular
Dense Regular
REticular CT
Adipose |
|
|
Term
|
Definition
Dermis-Reticular layer
Nerve Sheaths
Organ Capsules |
|
|
Term
|
Definition
| Tendons, ligaments, aponeurosis |
|
|
Term
|
Definition
Primarily reticular fibers
Function: structural framework, support
Primary cell type- reticular cells
(ex. lymphatic organs, endo organs) |
|
|
Term
|
Definition
Primarily adipocytes
Quite vascular
Function: lipid storage (energy, cushion, thermoregulation) |
|
|
Term
|
Definition
| Increase # of cell types in cell tissue leads to greater healing potential (loose heals better) |
|
|
Term
|
Definition
| Increase vascularity = greater healing potential |
|
|
Term
| Specialized Connective Tissue |
|
Definition
|
|
Term
| 3 mechanisms of protection |
|
Definition
Surface protection (epithelium, mucus, acidic environments)
Acute Inflamation (non specific, covers area)
Immune response (Humoral and Cell Mediated) |
|
|
Term
|
Definition
Responds to invading bacteris
Mediated by B cells and plasma cells, some T cell involvement
Involves Antibody production |
|
|
Term
|
Definition
Responds to viruses, fungi, or foreign cells
Mediated by T cells
Does not depend on B cell Participation |
|
|
Term
| Functions of Immune System |
|
Definition
Storage of Lymphocytes
Increase # of Lymphocytes
Provide a nice environment for immunity |
|
|
Term
|
Definition
No or incomplete capsule
Humoral immunity |
|
|
Term
|
Definition
Have a capsule
Humeral and cell mediated immunities |
|
|
Term
|
Definition
Provide an environment where lymphocytes become immunoCompetent
Wx. Bone marrow, Thymus |
|
|
Term
|
Definition
Provide and environment where Lymphocytes can contact foreign antigens
Ex. Lymph nodes, Spleen, Diffuse lymphatics |
|
|
Term
|
Definition
Mucosal-Associated Lymphatic Tissue
Duffuse, humoral immunity
Under epithelium-Lymph nodule production
In Gastrointestinal, urogenital, and respiratory tracts
Lymph nodules - B cells dividing - Plasma cells - Antibody production |
|
|
Term
|
Definition
secreted onto free epithelial surfaces
Tears, saliva, gut lumen, nasal cavity
Important first line of defense
Antigen specific
Able to: Neutralize viruses, Neutralize bacterial toxins, decrease microbial attachment to host cells |
|
|
Term
|
Definition
Gut Associate Lymphatic Tissue
Subcatagory of MALT
Ex. Peyre's Patches in ileum of SI |
|
|
Term
|
Definition
Bronchial Associated Lymphatic Tissue
MALT subcategory
In Respiratory system |
|
|
Term
|
Definition
Have Epithelial folds
Pharyngeal Tonsils: Adenoids/Tonsils of Lushka. In root of Nasal Pharynx, only one
Tubal Tonsils: paired tonsils, in opening of auditory tubes in nasopharynx |
|
|
Term
|
Definition
Faucial Tonsils
Have Tonsilar Crypts
At boundary of oral cavity and oral pharynx |
|
|
Term
|
Definition
Found on posterior 1/3 of tongue
Associated with seromucus glands (which flush out the crypts)
In Oral Cavity |
|
|
Term
|
Definition
| Tonsillar ring in CT around openings to the digestive and respiratory systems |
|
|
Term
|
Definition
Strung along length of lymphatic vessels.
Common in neck, axilla, and groin.
Secondary Lymphoid organ
Filter Lymph (phagocytosis)
Humoral and Cell mediated Immunity: foreign antigen recognition and B&T cells |
|
|
Term
|
Definition
Dense irregular CT
Moderate thickness |
|
|
Term
|
Definition
Septa
More dense irregular CT
Can carry blood vessels |
|
|
Term
|
Definition
at recessed area
Artery, vein (blood in/out), and major efferent lymph vessel exits |
|
|
Term
|
Definition
Subcapsular Sinus - marginal sinus
Cortical Sinus - passes through cortex
Deep Cortical Sinus - paracortex region (thymus dependent zone)
Meddullary sinus - passes through the medulla |
|
|
Term
| Cells within all regions of sunuses are supported by a system of |
|
Definition
| Reticular fibers produced by reticular cells |
|
|
Term
|
Definition
Primary cell type: B Lymphocytes
Lots of macrophages
Reticular cells
Antigen preventing cells (dendritic cells) |
|
|
Term
|
Definition
phagocytosis
Humoral Immunity (response to a particular foreign antigen) |
|
|
Term
| Important structures in Cortex |
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Definition
Lymph Nodules; 2 types
Primary, without germinal centers (older active nodule, group of niave B cells witout activation)
Secondary; with a germinal center (B cells divide, response to a particular foreign antigen) |
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Term
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Definition
Primary cell type: T cells (lymphocytes)
Macrophages in cloning process
Reticular cells making reticular fibers
APC |
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Term
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Definition
Long term storage for T cells
cell mediated immunity
some humoral immunity
enlarge w/ t cell activity |
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Term
| Important structures in paracortex |
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Definition
HEV: High epithelial Vessels
lining of cuboid-like cells that ferry B and T cells through vessel wall into the lymph node |
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Term
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Definition
Primary Type: Plasma Cells
Macrophages
Reticular Cells
Some ARC, B, and T cells |
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Definition
Phagocytosis (lymph cleaning)
Cell mediated immunity
* humoral immunity (antibody generation) |
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Term
| Important structures in Medulla |
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Definition
Medullary sinuses: for lymph fluid passage
Meddullary cords: aread between sinuses |
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Term
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Definition
Primary Lymphoid organ
Little funtionin left by age 25
Involution (atrophy and fatty infiltration) begins after first years, speeds up at puberty. |
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Term
| Spread of Fatty Infiltration of Thymus |
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Definition
1st: septa
2nd: Cortex
3rd: Medulla |
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Term
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Definition
Establish immunocompetent T lymphocytes able to :
distinguish self from non self
develop self tolerance |
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Definition
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Term
| Structural Characteristics of Thymus |
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Definition
Thin delicate capsule
Lobules with a peripheral cortex and central medulla |
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Term
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Definition
Capsule
Septa
Adipose
Microstroma=epithelial reticular cells AKA epithelioreticular cells |
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Term
| Epithelial Reticular Cells |
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Definition
6 types
Do not produce reticular fibers!
Offer support using long cytoplasmic extensions
Secrete thymic hormones and cytokines
Form thymic corpuscles
Important component of blood thymic barrier
Present self antigens to developing T Lymphocytes |
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Term
| Influence of cytokines and thymic hormones released by Epithelial reticular cells |
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Definition
T cell maturation
T cell division
Acticities
Expression of surface markers |
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Term
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Definition
Formed by epithelial reticular cells
AKA Hassal's bodies
Always in medulla
Increase in size with age
Increase in number with age
Unknown function! |
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Term
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Definition
Formed in part by epithelial reticular cells
Consists of: continuous capillary, Thick basal lamina, Epithelial reticular cells
Only found around cortical capillaries
allow self molecules through (to develop self tolerence) but they prevent blood bourne foreign molecules from entering area of t cell maturation |
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Term
| Functioning regions of the Thymus |
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Definition
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Term
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Definition
Stains darker because larger # of cells
Large # of T-cells (becoming immunocompetent and dividing)
Many macrophages
Epithelial reticulocytes types I, II, and III.
APC's |
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Term
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Definition
Stains lighter (fewer cells)
Some T cells (many immunocompetent, some still maturing) |
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Term
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Definition
T lymphocytes produced in bone marrow
Enter thymus as immunoincometent t cells
Leave blood at corticomedullary line
Migreate to periphery of cortex (T cells divide, mature, and are tested)
Migrate back toward medulla
Enter medulla as immunocompetent T cells
Leave thymus in post capillary venules or efferent lymph
Many to secondary lymphoid organs |
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