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CT Farmer Test 3

Cells and Tissues - Dr. Farmer - Test 3

Circulatory System Function Distribution of nutrients/hormones; Transport of waste to excretory organs
Lymphatic Circulatory System Lymph capillaries-closed-ended tubules; Lymph vessels; Empty to large vv. of circulatory system
Blood Circulatory System Heart-pump; Arteries-blood away from heart, get smaller away; Capillaries-more numerous, thin-walled, exchange b/t blood and tissue; Veins-blood to heart, progressively larger
Heart 4 Chambers-R and L atria-thinner-walled, receive blood from system(R) or lungs (L); Ventricles-thicker walled, distribute blood to lungs(R) or system(L); Valves maintain unidirectional flow, AV valves, pulmonary valve, aortic valve
Circulations Pulmonary-R side of heart, sends deoxygenated blood from heart to lungs; Systemic-L side, sends oxygenated blood to all tissues
Cardiac Skeleton Central region of heart surrounding valves, Dense CT, may calcify in older adults, provides support for valves and great vessels; Anchors cardiac m.; Annuli fibrosae surround valves; Trigona fibrosae-masses b/t annuli; Septum membranceum-part of IV septum
Heart wall 3 layers-Endocardium-inner, lined with endothelium, subendothelium is loose CT, subendocardial-CT, nn., Purkinje fibers; Myocardium-middle, thickest layer, muscle, fibrous; Epicardium-outer, serous layer, mesothelium, Loose CT, vv, nn,ANS ganglia, adipose
Generation and conduction of impulse for heartbeat Modified cardiac m. cells; SA node-wall of R atrium near SVC, cells spontaneously depolarize and initiate impulse, internodal tracts connect SA and AV nodes, IV bundle of His-Purkinje cells, L and R bundle branches-Purkinjes-conduct to apex and contracts
Blood vessels Tunica Intima-inner; Tunica Media-middle; Tunica Adventitia-outer
Tunica Intima Inner layer, endothelium lined, subendothelial CT, internal elastic lamina (in aa.)
Tunica Media Middle layer-concentric layers of smooth m., elastic fibers, reticular fibers, proteoglycans, external elastic lamina (larger aa.)
Tunica Adventitia Longitudinally arranged type I collagen, elastic fibers, continuous with CT of surrounding organs
Vasa Vasorum In walls of larger vessels, provide nutrition for outer layers (media/adventitia) of large vessels, more frequently in vv.
Capillaries 7 to 9 microns diameter, single layer of endothelial cells resting on basal lamina, cells held by tight junctions, pericytes-in capillaries adn post-capillary venules, outside endothelial layer, after tissue injury can proliferate to rebuild vessels
Continuous capillaries Widespread in m., lung, CT, exocrine glands, n. tissue; no pores (fenestrae); pinocytic vesicles involved in transcellular transport
Fenestrated capillaries Endothelial cells with fenestrae (pores) and continuous basal lamina; where rapid exchange occurs; kidney, intestine, endocrine glands
Sinusoidal capillaries much larger diamerer, discontinuous endothelial wall with fenestrae, macrophages in gaps b/t endothelial cells, in liver, bone marrow, spleen
Anastomosing networks Connects arterioles and venules, flow through network regulated by metarteriole, precapillary sphincter
Portal systems 2 capillary buds separated by v. or a.; hepatic portal system-capillaries of gut drain to hepatic portal v. then empty to liver capillaries; kidney-glomerulus (capillary bed) drains to efferent arteriole then to peritubular capillaries
Aa. Wall thicker than vv.; transport blood from heart to tissue, resist changes in BP in larger aa.; regulate bood flow in arterioles, large aa, medium and small arterioles
Large aa. Elastic or conducting aa.; thick tunica intima, thick media-fenestrated elastic lamina, many layers of smooth m.; adventitia relatively thin
Medium aa. Distributing aa., muscular aa., media has more smooth m., less elastin, prominent internal and external elastic lamina
Small aa. and arterioles Tunica media 5 to 10 layers smooth m. in small aa., 2 to 4 layers in arterioles; adventitia-thin, blends in with surrounding CT
Vv. Returns blood from tissue to heart, lower BP than aa.; thinner walls and larger lumens than corresponding a.; endothelial lined valves for 1-way flow; venules-sm, med, and lg vv.; postcapillary venules-similar to capillaries, larger lumen
Large vv. Well-developed intima, thin media, thick adventitia-in vv. inferior to heart contains longitudinally arranged in bundles of smooth m.
Small and medium vv. thin media, well-developed adventitia, valves
Lymphoid system functions Return interstitial fluid to blood, filtration of lymph, filtration of blood, defense of body from invasion and damage by microorganisms and foreign substances
Lymphoid system components Lymph vascular system, lymph, lymphatic tissue, lymphatic organs-primary-bone marrow-origin of lymphocytes, thymus-maturation of T-lymphocytes; secondary-lymph nodes, spleen, tonsils
Lymph vascular system Lymph capillaries-closed-ended, lymph vessels-interrupted by lymph nodes, lymph trunks-empty into subclavian vv.
Lymphatic tissues Reticular cells, lymphocytes, Lymph nodules, Unencapsulated lymphoid tissue
Reticular cells Thymus-from endoderm, called epithelial-reticular cells, don't produce reticular fibers, participate in T-lymph maturation; Reticular cells of other lymph tissues-mesenchyme-mostly mesoderm, produce reticular fibers (Type III collagen)
Lymphocytes B cells-humoral immunity, differentiate into plasma cells which make antibodies, form nodules; T cells-cellular immunity, multiple subclasses-helper, suppressor, cytotoxic, memory, etc.; don't form nodules
Lymph nodules Unencapsulated aggregates of mostly B cells, primary nodules-uniformly dense staining, cells haven't been exposed to antigen; Secondary nodules-contain lightly stained central region (germinal center), cells responding to antigen, prolif into plasma cells
Unencapsulated lymphoid tissue Diffuse lymphoid tissue-B and T cells, lamina propria under mucosa-digestive, respiratory and urinary tracts; Peyer's patches-aggregates of unencapsulated nodules in ileum; appendix-numerous nodules
Tonsils Incomplete encapsulation in contact with epithelium; Waldeyer's ring in prox GI tract-palatine-paired-lat wall of oral pharynx, epithelium-strat squamous, non-keratinized with crypts; pharyngeal-single-sup, post pharynx-PCCE, hypertrophy produces adenoids
Lingual tonsils Numerous-base of tongue-epithelium is strat squam, non-keratinized
Lymph nodes In-line filters of lymph, afferent/efferent lymphatics, stroma, parenchyma, lymph circ., blood circ.
Lymph node stroma Hilum-aa. and nn. enter, vv. and lymphatics exit; Capsule and trabeculae of CT, subcapsular sinus and peritrabecular sinuses, reticular cells and fibers
Lymph node parenchyma Cortex-nodules of B cells, paracortex-accumulations of T cells; medulla-cellular cords and sinuses-cords mostly B cells with some plasma cells, sinuses partly lined with macrophages and reticular cells
Lymph node lymph circulation Afferent lymphatics, subcapsular sinus, peritrabecular sinuses, medullary sinuses, efferent lymphatics
Lymph node blood circulation Aa. enter at hilum, branch into stroma, capillaries in cortex, post-capillary venules in paracortex-lymphocytes exit blood to reside in node, vv. exit at hilum
Thymus Lobulated, size varies with age, capsule with trabeculae delineates lobules, each lobule has medulla/cortex, stroma; parenchyma, medulla, vascularization
Thymus stroma epithelial, reticular cells, no reticular fibers, cellular processes produce frameowrk supporting lymphocytes, secrete thymosin-for T cell differentiation
Thymus parenchyma Cortex-thymocytes-immature T cells-not immunocompetent, macrophages eat thymocytes (many)
Thymus medulla High concentration epithelial-reticular cells, larger lymphocytes, Hassall's corpuscles-unknown function, only in thymus
Thymus vascularization capillaries in cortex (sheath of epi-ret cells), blood-thymus barrier
Spleen Largest lymphoid organ, filters blood, destroys old RBCs, Produce activated lymphocytes in response to blood-borne antigens
Spleen stroma Capsule of dense CT, trabeculae carry nn. and aa. from hilum to splenic pulp; carries vv. and efferent lymphatics from pulp to hilum; Reticular CT
Spleen parenchyma Splenic pulp-white-around central aa., PALS-T cells, splenic nodules-B cells; red-splenic cords-cords of Bilroth, sinusoids, marginal zone-b/t red and white pulp
Cords of Bilroth reticular cells and fibers, macrophages, lymphocytes, blood cells
PALS Peri-arterial Lymph sheath-T cells
Red pulp sinusoids elongated endothelial cells, transversely arranged reticular fibers, macrophages b/t endothelial cells, incomplete basal lamina
Marginal zone B/t red and white pulp, lymphocytes-mostly B cells, macrophages act as antigen presenting cells, lymphocytes exit blood and enter white pulp
Spleen blood supply Trabecular aa., central aa-surrounded by lymphocytes, penicillar aa (arterioles), arterial capillaries, closed circ-arterial capillaries empty into red pulp sinusoids, open circ-end in splenic cords and blood must pass into sinusoid wall
Spleen blood supply con't Old RBCs lose flexibility and can't squeeze past endothelial cells; sinusoids, red pulp vv, trabecular vv. and splenic vv.
Immunity Ability of organism to respond to and repel invasion by foreign substances, innate and acquired
Innate immunity nonspecific, phys barriers, secretions with anti-microbial activity
Acquired immunity Immune response, specific-direct to specific agent, cells require presentation of foreign substance to responder, responder that produces antibodies, responder that destroys cells
Antigens Molecules recognized by imm cells, soluble or attached to cell, may be protein, polysaccharide, or lipid; epitope-specific portion of antigen recognized, usually 5 to 10 amino acids or sugar residues, antigen may have multi epitopes
Antibody characteristics Produced by plasma cells, glycoproteins of Ig family, soluble or attached to lymphocytes, recognize and bid to specific epitope
Antibody structure Multimeric protein-2 light chains and 2 heavy chains; Fc region; Fab region-antigen binding, hypervariable, 2 per molecule
Antbody classes IgM, IgG, IgE, IgA, IgD
IgM 1st antibody produced in initial immunity response, bound to B lymphocyte, stimulates clonal expansion and differentiation of plasma cells
IgG Most abundant antibody in blood, produced in late primary and secondary response, facilitates destruction of bacteria and viruses
IgE Fc region binds to receptor on mast cells and basophils, low levels in blood, antibody-mast cell coplex stimualtes release of histamine and other molecules
IgA In secretions-saliva, tears, etc.; enzyme resistant, active against bacteria and viruses
IgD Very low concentration, mostly bound to B lymphocytes
Lymphocyte Characteristics Multiple subpopulations, distributed by membrane proteins-cluster differentiation (CD) markers, many are receptors
T lymphocytes All have TCR (T cell receptors) on cell surface, only recognize epitopes bound to receptor (MHC) molecules on other cells, subpopulations distinguished by CD markers
CD4 Helper T cells-central to immune response
CD8 Cytotoxic T cells-cell-mediated response; T suppressor cells turn off response
B Lymphocytes IgM bound to surface with Fab fragment exposed, active when bound to recognized epitope, clonal expansion-prolif of active B cells, differentiated into plasma cells and memory B cells, anamnestic response-powerful response to secondary exposure
MHC Integral membrane proteins, combined with peptides from viruses or other foreign substances, display foreign antigens on cell surface, MHC I, MHC II
MHC I on all cell surfaces, present antigen to cytotoxic T cells
MHC II found on antigen presenting cells-macrophages, dendritic cells, activated T cell, etc.; presentation to helper T cell is central to coordination of immune response
Antigen processing Macrophage-ingestion/partial digestion of foreign substance, presentation of foreign material on surface by MHC II, T cell-recognizes MHC II-antigen complex, binds to macrophage, activates cytotoxic T Cells, activates B cell to create plasma/antibodies
Phagocytosis Cells-neutrophils, macrophages, Langerhan's, dendritic cells; remove bacteria by neutrophils, margination-attration of circulating neutrophils-endothelial cells secrete attractant molecules, neutrophils slow and adhere to endothelium
Diapedesis movement of neutrophils b/t endothelial cells into CT
Digestive System Functions Ingest, digest, absorb food
Digestive system components Oral cavity, pharynx, esophagus, stomach, small and large intestines, rectum, anus
Associated digestive glands Salivary glands, liver, pancreas
General Structure Tueb with 4 layered wall-mucosa, submucosa, muscularis externa, serosa/adventita
Mucosa Selective barrier, secretion/absorption, epithelium, lamina propria-loose CT, muscularis mucosa-smooth m.
Submucosa Loose CT, blood and lymphatic vessels, Meissner's plexus-part of ANS, glands in esophagus and duodenum
Muscularis externa Usually 2 layers smooth m. Auerbach's plexus-part of ANS
Serosa/Adventitia Adventitia in areas where organ is embedded in other tissue; Serosa with mesothelium where there is a free surface
Esophagus Transports food from mouth to stomach; mucosa-strat squam nonker; submucosal glands make mucus; muscularis externa-upper 1/3 skeletal, mid 1/3 both; lower 1/3 smooth m.; adventitia above diaphragm; serosa below diaphragm
Stomach functions Convert ingested food to acidic chyme; exocrine-secretes pepsin, endocrine-secrete hormones
Stomach regions Cardia, fundus/body-histologically identical, pylorus
Rugae Longitudinal folds of mucosa/submucosa, non permanent-disappear when stomach fills
Stomach mucosa Pits/glands; cells-stem cells-in neck region, mucous neck cells, parietal cells-HCl and intrinsic factor, chief cells-zymogenic granules contain pepsinogen and gastric lipase, enteroendocrine cells
Stomach muscularis externa 3 layers-inner oblique, middle circular, outer longitudinal
Small intestine functions Final digestion, absorption, endocrine secretion
3 segments of small intestine Duodenum, jejunum, ileum
Small intestine mucosa Structures to increase surface area-plicae circularis-perm folds of mucosa/submucosa, villi, microvilli; crypts of Lieberkuhn; cells of mucosa; Peyer's patches in lamina propria of ileum
Small intestine cells of mucosa Intestinal absorptive cells-enterocytes; columnar epi with microvilli; Goblet cells-protect/lubricate, increases in # as approach ileum; Paneth cells-base of crypts, secrete lysozyme; Enteroendocrine cells-CCK-stim pancreas/gallbladder(secretin-stim panc)
Small intestine submucosa Brunner's glands in duodenum secrete alkaline mucus
Large intestine functions Absorb H2O, produce mucus, form feces
Large intestine components Cecum, Ascending colon, descending colon, transverse colon, sigmoid colon, rectum
Large intestine mucosa No villi, glands of lieberkuhn (absorptive cells, goblet cells), extensive diffuse lymphoid tissue in lamina propria
Large intestine muscularis externa Outer longitudinal layer-3 bands called tenaie coli
Rectoanal junction Mucosa-epithelium changes abruptly from simple columnar to strat squam nonker, muscular mucosa disappears; submucosa-hemorrhoidal vv.; muscularis externa-inner circular layer forms internal anal sphincter
Salivary glands Parotid, submandibular, sublingual
Saliva Lubricates food, initiates digestion of carbs, immune function-secretes IgA and lysozyme
Salivary gland structure CT capsule, lobules, serous acini, mucous, acini, myoepithelial cells-highly branches contractile cells within basal lamina
Salivary gland ducts Intercalatedo-initial segs, simple cuboidal; striated-intralobular-cub to columnar, excretory-interlobular-strat cub to strat col; main duct empties to oral cavity-strat squam nonker.
Salivary gland innervation By ANS, parasympathetic stimulates large amount of watery secretion, low protein; sympathetic stimulates small amount viscous saliva rich in organic material
Parotid gland Largest gland, compound acinar, serous only-granules high in amylase; plasma cells in CT add IgA
Submandibular gland Compund tubuloacinar gland, mucous and serous cells, serous demilune secrete lysozyme
Sublingual gland Compund tubuloacinar gland, serous and mucous cells, serous cells only in demilunes
Pancreatic structure Thin CT capsule with septa (divides into lobules), regionally divided into endo and exocrine glands, endocrine-islets of Langerhans (2% of total gland), exocrine-compound acinar gland
Pancreas-exocrine portion Serous secretory units- digestion enzymes, duct system, secretions, hormonal control
Exocrine duct system centroacinar cells-penetrate acinus, intercalated ducts secrete HCO3 to neutralize chyme in intestine, main excretory duct-duct of Wirsung; accessory duct-duct of Santorini
Exocrine secretions Trypsinogen, carboxypeptidase, chymotrypsin, amylase, lipases, ribonuclease, deoxyribonuclease
Exocrine hormonal control Chyme in duodenum stimulates enteroendocrine cells to release secretin and CCK-secretin-duct cells make HCO3, CCK-acinar cells-make digestive enzymes
Endocrine-Islets of Langerhans Alpha cells make glucagon to increase blood glucose levels; Beta cells make insulin to decrease blood glucose levels; Delta cells make somatostatin, inhibits secretion of glucagon and insulin; PP cells (F cells) block CCK, decrease enzymes
Liver Stroma Thin CT capsule (Glisson's capsule), hilum-portal v. and hepatic a enter, hepatic ducts and lymphatics exit; reticular CT
Liver functional units Classic liver lobule, liver acinus, portal lobule
Classic liver lobule Central v, portal areas at periphery-portal v, hepatic a, bile duct; hexagonal; dual blood supply-hepatic portal v (80%), nutrient rich from intestinal tract, blood from spleen, hepatic a (20%)-branch from celiac trunk, well-oxygenated blood
Liver sinusoids Specialized large capillary, discontinuous fenestrated endothelial cells, Kupffer cells-macrophages; Space of Disse-b/t endothelial cells and hepatocytes
Hepatocytes Functional units of liver, plates of cells, polyhedral, apical surface open to sinusoids, basolateral surfaces attach to other hepatocytes
Bile ducts Drain bile from hepatocytes, bile canaliculus, Hering's canal, bile ducts of portal triads, L and R hepatic ducts, common hepatic duct, cystic duct, common bile duct
Liver function Endocrine-plasma proteins, exocrine-bile production, metobolite storage-lipids as triglycerides, carbs as glycogens, vitamins-especially Vit. A; produces urea from deamination of amino acids, detox and inactivation of drugs
Gall bladder function Concentrate bile, store bile
Gall bladder structure Mucosa-simple columnar, no submucosa, CT binds to surface of liver, free surface covered with serosa
Integument function Mechanical protection, protection from fluid loss, physical barrier, thermoregulation, receptor organ
Integument Structure Epidermis-from surface endoderm, strat squam ker epithelium; Dermis-mostly mesoderm, dense irregular CT; hypodermis-not truly skin-loose CT, forms superficial fascia
Epidermis 2 types, 5 layers, 3 cell types, pigmentation
Epidermis types Thick-glabrous, smooth, nonhairy; Thin-hairy
Stratum basale 1 layer thick, rests on basal lamina, highly mitotic, cuboidal to columnar cells
Stratum spinosum Cuboidal cells, extensive desmosomes-"prickle cells", tonofilaments-keratin
Stratum granulosum Keratohyalin granules-protein-no membrane, lamellar bodies-lipid, membrane-bound, sealant effect-waterproof, cells above die
Stratum Lucidum Only in thick skin
Stratum Corneum Dead cells, no organelles, high molecular weight keratin tonofilaments
Epidermal cell types Keratinocytes-predominate; Langerhan's-originate in bone marrow, antigen-presenting cells; Melanocytes-from neural crest, make melanin, transfer melanin to cells of stratum basale and stratum spinosum
Epidermal pigmentation Blood, carotene, melanin
Dermis Structure Dense irregular CT, variable thickness, type I collagen and elastic fibers-provide strength/elasticity; fibroblasts/macrophages; Ground substance-high in hyaluronic acid, dermatan sulfate and chondroitin sulfate
Dermal layers Papillary dermis, reticular dermis
Dermal blood supply Arterial and venous plexuses b/t papillary and reticular dermis and b/t reticular dermis and hypodermis; Arteriovenous shunts can bypass superficial capillaries to conserve heat and increase BP
Dermal n. endings Encapsulated-Meissner's corpuscles-in papillary dermis, touch; Pacinian corpuscles-depp dermis and hypodermis; deep pressure and vibration; Free-fine touch, temp; abundant around hair follicles
Sweat glands Eccrine, wide distribution, simple, coiled tubular glands, secretory cells-simple cuboidal; duct-strat cuboidal, merocrine secretion
Hair In thin skin, hair follicle-epidermal region; sebaceous gland-outgrowth of hair follicel, secretes sebum into follicle, holocrine secretion
Arrector pili m. Smooth m. innervated by sympathetic division of ANS, contraction causes hair to stand up
Respiratory system functions Conducts air for gas exchange, conditioning of air-clean, moisten, warm; respiration-gas exchange b/t air/blood
Respiratory General Structure Tubes leading to lung, Lungs
Conducting passages Conduct air only, nasal cavity, nasopharynx, oropharynx, larynx, trachea, extrapulmonary/intrapulmonary brochi, bronchioles, terminal bronchioles
Respiratory passages Respiratory can take place, respiratory bronchioles, alveolar ducts, alveolar sacs, Alveoli
Larynx Function Conduct air to trachea, generate speech
Larynx structure Cartilages-hyaline and elastic, PCCE, epiglottis, vocal folds
Epiglottis Separates larynx/pharynx, prevents food from entering trachea, elastic cartilage, strat squam nonker epi on lingual surface, PCCE on laryngeal surface
False vocal cords PCCE, numerous glands in lamina propria
True vocal cords Strat squam nonker epi, no glands, vocalis m. (skeletal) and vocal ligament
Trachea Larynx to midthorax, mucosa-PCCE w/ goblet cells, prominent basement membrane; submucosa-combined w/ lamina propria, serous glands; Hyaline cartilage-16 to 20 C rings open posteriorly, ends connected by trachealis m. (smooth)/fibroelastic lig, adventitia
Bronchi Extrapulmonary-1 to each lung, enter lung at hilum; Intrapulmonary-inside lung, multiple divisions; same structure as trachea, within lung-cartilage in plates, PCCE, smooth m.
Bronchioles PCCE with goblet cells, no cartilage or glands, smooth m.
Terminal bronchioles Simple columnar ciliated epithelium, no goblet cells, Clara cells-non-ciliated, secretory; smooth m. and elastic fibers
Respiratory bronchioles Alveoli interspersed in walls, cuboidal ciliated epithelium, Clara cells, smooth m. and elastic fibers
Alveolar ducts Smooth m., b/t adjacent alveoli
Alveolar sacs Clusters of alveoli at end of alveolar ducts
Type I cells Very thin squamous epithelium, majority of alveolus wall
Type II cells In corners of alveoli, secrete surfactant
Alveolar septum Wall b/t adjacent alveoli, alveolar epithelium, basal lamina, capilalries, CT cells-fibroblasts/mast cells, reticular fibers, macrophages-"dust cells", also in alveolar spaces
Alveolar pores B/t adjacent alveoli, equalize air pressure
Blood-air barrier Alveolar epithelium (Type I cells), capillary endothelium, fused basal lamina
Blood supply Dual-nutrition of lung, oxygenation of blood; Pulmonary circulation-oxygenation of blood, pulmonary aa. to capillaries around each alveolus to pulmonary vv.; Bronchial circulation-typical systemic circulation, extends to resp. bronchioles, anastomoses
Created by: lkeith
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