Term
| Structural Components of the Lymph System |
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Definition
Lymph Vessels (capillaries, vessels, trunks, ducts)
Lymph Tissues & Organs (Nodes, Spleen, Thymus) |
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Term
| Difference between ISF and lymph |
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Definition
ISF = fluid that exists in interstitium
Lymph = ISF that has been taken into a lymph vessel |
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Term
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Definition
| Towards the heart (lymphatics form a one-way vessel system) |
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Term
| Lymph capillaries are found everywhere except... |
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Definition
| Bone, bone marrow, cartilage, CNS |
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Term
| What makes lymphatic capillaries so permeable? |
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Definition
Overlapped endothelial cells in wall (don't have tight junctions), which can form easily opened flaps.
Bundles of filaments anchor endothelium to CT; when ISF volume (pressure) increases, the flaps allow for the ONE WAY opening of the flaps between endothelial cells for the lymph to enter the vessels; filaments also prevent vessel collapse |
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Term
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Definition
Similar to veins in structure, but have MORE valves; this is due to the decreased pressure in the lymphatic system (no central pump)
To pump lymph through the vessels, the major reliance is on the skeletal muscle pump (contraction of surrounding muscles pushes lymph towards heart) |
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Term
| Superficial and deep lymphatic collecting vessels merge to form... |
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Definition
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Term
| Types of Lymphatic Trunks in the Body |
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Definition
Lumbar, Intestinal, Bronchomediastinal, Jugular, Subclavian
All are paired trunks; similar to veins in structure |
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Term
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Definition
2 exist in the body: R lymphatic duct, and thoracic duct
Receive lymph from respective lymphatic trunks |
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Term
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Definition
Collects lymph from the R side of the body above the diaphragm
Drains into the junction of the R subclavian and R internal jugular veins |
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Term
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Definition
Begins at the level of L1-L2 @ CISTERNA CHYLI (receives lymph from intestinal and lumbar trunks); travels upwards and empties into the L subclavian vein before it joins with the L internal jugular vein
Collects lymph from both sides below the diaphragm and the L side above the diaphragm |
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Term
| Two main types of lymphoid cells: |
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Definition
Macrophages - differentiated (mature) monocytes; involved in the phagocytosis of pathogens & debris
Lymphocytes - agranular leukocytes involved in cell mediated and antibody mediated immunity |
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Term
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Definition
| T cells (80%), B cells (15%), NK cells (5%) |
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Term
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Definition
Function to manage immune response; some can directly attack antigen; responsible for CELL mediated immunity
Cytotoxic T cell - warriors; directly attack and destroy antigens
Helper T / Suppressor T cells - assist in coordination of immune response; control B cell differentiation; suppressor T can shut down cytotoxic T cells ("off switch")
Memory T cell - remembers antigen; if reintroduced to body, 1st to respond |
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Term
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Definition
Protect body by ability to produce antibodies; responsible for ANTIBODY mediated immunity
B cells activated by exposure to antigen, can differentiate into PLASMA cell
Helper T - promote differentiation of B cells
Suppressor T - inhibit differentiation of B cells
Memory B cells - same function as memory T |
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Term
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Definition
| Can directly attack antigens; do not need to be stimulated or activated to function; "immunoserveillance cells" |
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Term
| Variations of Lymph Tissue |
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Definition
Diffuse Lymph Tissue - scattered elements of reticular CT; found in mucous membranes & lymph organs
Lymph Follicles/Nodules - solid accumulation of reticular CT; germinal centers contain mature differentiating B cells (into plasma cells) |
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Term
| Locations of Lymph Nodules/Follicles |
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Definition
Digestive tract (GALT)
In the pharynx and oral cavity as TONSILS (pharyngeal, palatine, lingual)
Beneath mucosa of Ileum (Peyer's patches)
Appendix |
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Term
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Definition
Composed of diffuse lymph tissue and/or lymph follicles AND enclosed by a capsule of dense CT
Examples - lymph nodes, thymus, spleen |
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Term
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Definition
Function is to filter lymph as it passes through circulation and activate immune response
Bean-shaped; 1mm-2.5cm in length
3 main locations - cervical, axillary, inguinal |
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Term
| Capsule Structure of Lymph Nodes |
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Definition
| Nodes are surrounded by fibrous CT capsule; portions project inwards (TRABECULAE) to separate the cortex of the node into smaller areas |
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Term
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Definition
| Divided by trabeculae of cortex; foundation of diffuse lymph tissue and is scattered with lymph follicles (containing differentiating B cells @ germinal centers) |
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Term
| Deep Cortex of Lymph Nodes |
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Definition
| Found in between cortex & medulla; location of T cells in the nodes |
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Term
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Definition
Primarily made of MEDULLARY CORDS (extensions of diffuse lymph tissue from cortex)
Find B cells + plasma cells |
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Term
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Definition
Afferent lymphatics deposit lymph into the subcapsular sinus; lymph passes from subcapsular sinus, into trabecular sinuses, and finally into medullary sinuses
From here it drains into the hilus of the node, where it is taken away by efferent lymphatics |
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Term
| Path of lymph travelling through a lymph node |
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Definition
| Enters @ subcapsular sinus from afferent lymphatics; dendritic cells in diffuse lymph tissue trap pathogens and debris until they can be removed by macrophages; lymph continues through trabecular and then medullary sinuses before being emptied into the hilus and carried away by efferent lymphatics |
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Term
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Definition
Lymph organ located in the upper mediastinum; anterior to the great vessels of the heart
Size peaks during adolescence, then is gradually replaced by fatty CT
Function is to secrete hormones to stimulate maturation of stem cells into immunocompetent T cells |
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Term
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Definition
Divided into 2 lobes; lobes are subdivided into lobules by septae
Contains a cortex and a medulla
Foundation is NOT diffuse lymph tissue; made of EPITHELIAL RETICULAR CELLS |
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Term
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Definition
Stem cells migrate here from the bone marrow; only some mature into T cells
Cortex is impermeable to blood (blood-thymus barrier) to prevent early exposure of antigens to immature T cells
Mature T cells are believed to enter circulation at the cortex-medulla interface
T cells in the cortex are NOT involved in the immune response |
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Term
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Definition
Also based on epithelial reticular cells; clusters of these cells = Hassal's corpuscles (unknown function)
Also believed that mature T cells will migrate here following differentiation |
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Term
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Definition
Largest lymph organ in the body; L side of abdomen, inferior the diaphram between the stomach and the kidney
Covered by a dense CT capsule, but trabeculae DO NOT divide the spleen into lobes/lobules; no distinct cortex or medulla
Functions to filter and store blood, and activate the immune system |
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Term
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Definition
Diaphragmatic - smooth superior surface contoured to diaphragm
Visceral - medial surface; indentation for stomach and kidney (gastric and renal areas); knuckles represent the gastric area
Hilum of the spleen exists at the border between the gastric and visceral areas (entrance/exist for splenic vein and artery); note - splenic artery is highly coiled, splenic vein is not |
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Term
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Definition
White Pulp - contains lymphatic follicles and activates immune system
Red Pulp - filters and stores blood |
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Term
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Definition
Consists of lymphatic nodules formed around a central artery
Germinal centers contain plasma, B, and T cells |
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Term
| Functional Regions of the Respiratory System and their Functions |
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Definition
Conducting Portion - from nasal cavity to terminal bronchioles; functions as a conduit for air, also conditions air (warm, humidify, filter)
Respiratory Portion - from respiratory bronchioles to alveoli; site of gas exchange |
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Term
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Definition
| Pseudostratified ciliated columnar epithelium w/ goblet cells; conditions inspired and expired air; only found in conducting portion |
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Term
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Definition
Primary pathway for air entering system
Nasal cavity divided into 2 by a nasal septum - anterior = hyaline cartilage; posterior = bone (ethmoid + vomer) |
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Term
| Boundaries of the Nasal Cavity |
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Definition
Roof = ethmoid, sphenoid, frontal bones
Floor = palate
Walls = maxillary bones |
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Term
| Regions of the Nasal Cavity |
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Definition
Vestibule - portion directly behind external nares
Fossae - includes the superior, middle, inferior nasal conchae |
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Term
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Definition
Superior, middle, inferior
Exist to condition the air; structure allows them to act as turbines to mix the air and condition thoroughly
Normal RTE in inferior & middle; in superior RTE, NO goblet cells, instead contains olfactory epithelium involved in smell |
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Term
| Process of Air Conditioning by RTE |
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Definition
Warm - heat from underlying BVs warms RTE, which transfers heat to inspired air
Humidify - lamina propria and serous membranes secrete fluid
Filter - cilia and mucous in vestibule and fossae |
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Term
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Definition
Ethmoid, Sphenoid, Frontal, Maxillary
Spaces in bones ALL connected by narrow passage to nasal cavity
Lined with RTE (aid in conditioning) |
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Term
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Definition
Connects nasal & oral cavities to larynx & esophagus
Functions for food & air
Wall is made of skeletal muscle (pharyngeal constrictors)
3 regions - naso, oro, laryngo |
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Term
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Definition
From posterior nasal cavity to level of soft palate
Lined with RTE (functions only for air)
Contains opening to Eustachian tubes in lateral walls, and pharyngeal tonsils in posterior wall |
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Term
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Definition
From the level of the soft palate to the base of the tongue (epiglottis)
Lined with stratified squamous epithelium; used for food and air |
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Term
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Definition
From the base of tongue (epiglottis) to the beginning of the larynx
Lined with stratified squamous epithelium; food + air
Continuous with the esophagus |
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Term
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Definition
Functions to connect the laryngopharynx to the trachea, and produces sound; made of 9 cartilages (thyroid, cricoid, epiglottis, corniculate, cuneiform, arytenoid)
Larynx moves UP while swallowing so epiglottis covers opening (prevents food from entering) |
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Term
| What cartilages form the body of the larynx? |
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Definition
| Thyroid cartilage, Cricoid cartilage, Epiglottis |
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Term
| What cartilage anchors the vocal ligaments? |
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Definition
| The arytenoid cartilage (vocal ligaments connect arytenoid and thyroid cartilages) |
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Term
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Definition
Inferior to false vocal cords; includes vocal ligament + fold; produce sound
Space between folds = GLOTTIS |
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Term
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Definition
| Located superior to true vocal cords; consists of vestibular ligament + fold |
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Term
| Epithelium of the larynx? |
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Definition
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Term
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Definition
Aka Windpipe; connects larynx to the mediastinum
Divides into primary bronchi at carina at level of T4-T5
3 main histological layers - mucosa, submucosa, adventitia |
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Term
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Definition
Mucosa = RTE + lamina propria
Submucosa = dense irreg CT + mucous glands
Adventitia = CT internally reinfored by C-shaped rings of hyaline cartilage
Trachealis = layer of smooth muscle at posterior trachea; connects hyaline rings and allows for expansion or compression of the trachea |
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Term
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Definition
Also known as EXTRApulmonary bronchi (outside lungs); 1 goes to each lun
R primary bronchus - wider, shorter, more vertical (more food gets stuck here)
Bronchi enter lungs at hilus (roote of lung) on oblique angle |
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Term
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Definition
Parietal Pleura - lines inside of thoracic wall (lateral mediastinum) and superior diaphragm
Visceral Pleura - directly lines the lungs
Both are serous membranes and secrete pleural fluid to lubricate lungs |
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Term
| Surfaces/Features of the Lungs |
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Definition
Apex (Cupola) - anterior portion of lung that projects into the neck area
Diaphragmatic (Base) - sits on diaphragm
Costal - anterior, posterior, lateral surfaces
Medial - hilus (root) of lung; L lung contains cardiac notch on medial surface |
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Term
| Differences between R and L lung: |
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Definition
R lung - shorter than L lung due to liver pushing up on diaphragm; 3 lobes, 2 fissures (horizontal = superior from middle; oblique = superior & middle from inferior)
L lung - smaller than R lung due to presence of heart and great vessels; 2 lobes, 1 fissure (oblique) |
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Term
| Segmentation of the Lobes |
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Definition
Lobes are broken down into bronchopulmonary segments; each is separate identity (individual vessels, nerves, lymphatics)
Segments are further subdivided by CT to form pulmonary lobules (each is individual as well)
Can remove an individual lobule or segment without interfering with the structural or functional integrity of the lung |
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Term
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Definition
Primary Bronchi - 1 to each lung
Secondary (Lobar) Bronchi - 1 to each lobe (3 to right, 2 to left)
Tertiary (Segmental Bronchi) - 1 per bronchopulmonary segment, 10 to each lung (R = 3, 2, 5; L = 5, 5)
Terminal Bronchioles - supply individual pulmonary lobules |
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Term
| Histological Transitions of Bronchial Tree |
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Definition
- As the bronchi subdivide, the amount of cartilage decreases; NO cartilage in terminal bronchioles
- Epithelium Transitions - RTE -> ciliated simple columnar -> ciliated simple cuboidal -> simple cuboidal (in bronchioles)
- Relative amount of smooth muscle in walls increases as segmentation increases |
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Term
| Respiratory Portion of the Lungs |
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Definition
Respiratory Bronchioles - cuboidal; branch from terminal bronchioles; contain increasing amounts of alveoli
Alveolar Ducts - contain only alveoli in their walls; end in blind-ended alveolar sacs |
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Term
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Definition
Site of gas exchange in the lungs
Type I cells - simple squamous epithelium; endothelium
Type II cells - cuboidal surfactant cells; lamellar bodies in type II cells produce surfactant
Alveolar Pore - holes in alveoli to connect adjacent ones which serve to equalize air pressure
Interalveolar Septum - consists of the respiratory membrane as well as interstitium |
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Term
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Definition
Type I cell (endothelium) + lamina propria of alveoli and capillary + capillary endothelium
This is the membrane that air must cross to diffuse into the capillaries |
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Term
| What are the most important muscles of respiration? |
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Definition
| Diaphragm + external/internal intercostals |
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Term
| Diaphragm (mechanics of breathing) |
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Definition
Contract = increase volume of thoracic cavity (inspire)
Relax = decrease volume of thoracic cavity (exhale) |
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Term
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Definition
External = contract to elevate the rib cage to increase volume during inspiration
Internal = contract to depress ribcage which decreases volume during expiration |
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Term
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Definition
Eupnea = quite breathing; inspiratory muscles are used, but expiration occurs passively
Hypnea = forced breathing; involves active inspiratory and expiratory movements |
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Term
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Definition
Diaphragmatic Breathing - deep breathing; uses mainly the diaphragm
Costal breathing - shallow breathing; uses mainly the intercostals |
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Term
| Regulatory Centers for Respiration |
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Definition
Respiratory Rhythmicity Center - located in the medulla; sets pace and depth; DRG = inspiration (always functioning); VRG = only functions during hyperpnea (forced breathing)
Apneustic & Pneumotaxic Centers - in pons; regulate output of rhythmicity center |
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Term
| Epithelium of Oral Cavity? |
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Definition
| Oral Mucosa = strat. squamous epithelium (non-keratinized) |
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Term
| Components of the Oral Cavity: |
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Definition
Vestibule - space located between lips & cheeks, and gums & teeth; initial location of food
Oral Cavity Proper - main component of the mouth; lateral walls = alveolar arches; roof = palate; floor = tongue |
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Term
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Definition
Hard Palate = anterior portion (bony)
Soft Palate = posterior portion (skeletal muscle); uvula is the extension of distal soft palate (used in pronunciation)
During swallowing, soft palate elevates to close off nasopharynx |
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Term
| Fauces (Anterior + Posterior) |
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Definition
Anterior = Palatoglossal Arch; from palate to tongue
Posterior = Palatopharyngeal Arche; from palate to pharynx
Palatine tonsils exist in between the anterior and posterior arches |
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Term
| What connects the tongue to the floor of the mouth? |
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Definition
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Term
| Intrinsic Muscles of the Tongue |
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Definition
Have origins and insertions on the tongue; involved in altering the shape of the tongue (e.g. tongue-roller)
Run in 3 directions - longitudinal, transverse, vertical
Innervated by CN XII (hypoglossal) |
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Term
| Extrinsic Muscles of the Tongue |
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Definition
3 main muscles - Styloglossus, Hyloglossus, Genioglossus
Function in the main movements of the tongue
All innervated by CN XII |
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Term
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Definition
o = posterior mangible; i = tip of tongue
Paired muscle; each muscle pulls the tongue to the opposite side (R genioglossus moves tongue to the left, and vice versa)
If CN XII has a lesion, the direction the tongue points to is the side of the lesion (e.g. lesion of L CN XII, tongue will point to left because only the R genioglossus can contract) |
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Term
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Definition
o = styloid process of temporal bone; i = tongue
Pulls tongue upwards, pulls tongue inwards |
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Term
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Definition
o = hyoid bone; i = tongue
Pulls tongue downwards, pulls tongue inwards |
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Term
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Definition
Anterior 2/3 - BODY of the tongue; this is the mobile portion of the tongue
Posterior 1/3 - ROOT of the tongue; attached to hyoid bone; lingual tonsils are submucosal to the root
Body and root of tongue are separated by a fibrous septum |
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Term
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Definition
Projections of epithelium of the tongue; only on anterior 2/3 (body)
3 types - filliform, fungiform, circumvallate |
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Term
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Definition
| Located on distal body of tongue; elongated; composed of stratified squamous epithelium (keratinized) |
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Term
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Definition
| In the "middle" of the tongue; pinkish shaped mushroom looking projections; contain dorsal taste buds |
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Term
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Definition
| Located at the junction of the body & root of the tongue; only have 10-12; taste buds located in the wall of the trough |
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Term
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Definition
Taste buds contain approximately 40 taste cells (gustatory cells)
Gustatory cells have microvilli which project through taste pore to absorb food particles and send signals back to the CNS
Basal cells (produce new taste cells); supportive (transitional cells) also exist |
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Term
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Definition
Sweet, sour, bitter, salty, umami (savoury)
Also have discovered taste receptors for water |
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Term
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Definition
Minor glands - cheeks, tongue, lips
Major glands - parotid, submandibular, sublingual |
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Term
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Definition
Located anterior to the ears; parotid duct (Stenson's) travels anterior to the masseter to empty into the vestibule of the mouth opposite the 2nd upper molar
Secretes serous fluid (serous acini) as well as amylase |
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Term
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Definition
Located under the mandible; submandibular (Wharton's) duct crosses over mylohyoid to empty into the floor of the mouth near the lingual frenulum
Secretes serous fluid + mucous (serous and mucous acini) |
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Term
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Definition
| Paired glands located under the tongue; 10-12 sublingual ducts release mucous secretions into the floor of the mouth (mucous acini) |
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Term
| What is the functional unit of a salivary gland? |
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Definition
| Acinus (either mucous or serous) |
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Term
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Definition
20 in total
2 incisors, 1 canine (cuspid), 2 molars / half jaw |
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Term
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Definition
32 in total
2 incisors, 1 canine (cuspid), 2 premolars (bicuspid), 3 molars / half jaw |
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Term
| Eruption Times for Deciduous Teeth |
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Definition
6 months = 1st incisor
12 months = 1st molar
24 months = all teeth |
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Term
| Eruption Times for Permanent Teeth |
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Definition
6 years = 1st incisor and 1st molar
12 years = 2nd molar & all anterior to 2nd molar
24 years = wisdom teeth (3rd molar) |
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Term
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Definition
Crown = visible portion of tooth above gingiva
Root = part of tooth in alveolus
Neck = junction of crown & root (@ gingiva)
Dentin = calcified portion of the tooth
Enamel = hardest biological material; irreplaceable; outer layer of tooth |
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Term
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Definition
socket; alveolar bone teeth sit in
If a tooth is removed, the alveolus (alveolar bone) begins to recede |
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Term
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Definition
| "Gums"; Stratified squamous epithelium that covers the alveolus |
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Term
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Definition
| Loose CT deep to dentin; location of arteries, veins, nerves |
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Term
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Definition
| Entrance of vessels and nerves into root canal; root canal directs vessels and nerves to pulp cavity |
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Term
| What is the narrowest portion of the pharynx? |
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Definition
| Laryngopharyx; this is because the larynx pushes into its anterior wall, compressing it |
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Term
| Pharyngeal Constrictor Muscles |
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Definition
Paired muscles; superior, middle, lower; skeletal muscle
Function to narrow the pharynx during swallowing which pushes the food towards the esophagus
Involved in the gag reflex
Innervated by CN IX (glossopharyngeal) |
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Term
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Definition
Buccal Phase (Voluntary) - food enters the mouth; teeth and tongue compress food and tongue pushes bolus towards the oropharynx
Pharyngeal (Involuntary) - soft palate elevates to prevent food from entering nasopharynx; pharyngeal constrictors contract to propel food to esophagus; larynx elevates so that epiglottis covers its opening
Esophageal (Involuntary) - muscles of esophagus propel food towards stomach via peristaltic waves |
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Term
| What is unique about the epiglottis/larynx during infancy? |
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Definition
| During infancy, the epiglottis is raised so it is visible in the oropharynx; during breastfeeding, the larynx elevates and connects to the nasopharynx so that the baby can breathe and swallow at the same time |
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Term
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Definition
Mucosa - surface epithelium (variable); lamina propria (loose CT); muscularis mucosa (smooth muscle)
Submucosa - dense irregular CT containing vessels, lymphatics, and glands; contains submucosal (Meissner's) plexus which innervates structures in mucosa and submucosa
Muscularis Externa - inner circular muscle layer, outer longitudinal muscle layer; between layers there is the myenteric (Auerbach's) plexus which innervates the layers
Adventitia or Serosa - adventitia = only CT; serosa = lined with peritoneum |
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Term
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Definition
Serous membrane secreting serous fluid (peritoneal fluid)
Visceral Peritoneum - lines the organs
Parietal Peritoneum - lines the abdominal wall
Mesentery - double layer of peritoneum |
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Term
| Intra vs. Retro Peritoneal |
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Definition
Intraperitoneal - organ is completely covered in peritoneum
Retroperitoneal - organ is covered only anteriorly by peritoneum; posterior is against the abdominal wall |
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Term
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Definition
Connects pharynx to the stomach; begins in neck, ends in abdominal cavity
In upper mediastinum, it is posterior to the trachea; in the lower mediastinum it is posterior to the L atrium. |
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Term
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Definition
Located at the level of T10; end-point of esophagus in the thoracic cavity
Located as a space in the diaphragm that the esophagus passes through to enter the abdominal cavity
Clinical Case -> Hiatus Hernia - when part of the stomach herniates through the hiatus |
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Term
| Histology of the Esophagus |
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Definition
Mucosa - stratified squamous epithelium + lamina propria + muscularis mucosa
Submucosa - dense irregular CT, mucous glands + submucosal (Meissner's) plexus
Muscularis Externa - inner circular, outer longitudinal; upper 1/3 = skeletal; middle 1/3 = skeletal and smooth; lower 1/3 = smooth
Adventitia - CT only; last 1-2 cm in abdominal cavity does have serosa (retroperitoneal) |
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Term
| Upper Esophageal Sphincter |
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Definition
Near junction of pharynx and esophagus; not a definitive sphincter; remains closed until swallowing, then relaxes
Involved in eruptation and sound production |
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Term
| Lower Esophageal Sphincter |
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Definition
| Located at the end of the thoracic esophagus (above hiatus); prevents reflux from stomach from entering the esophagus |
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Term
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Definition
Cardia - where esophagus joins to stomach
Fundus - elevated portion above cardia; sits in L dome of diaphragm and is usually filled with air
Body - main portion of stomach
Pylorus - distal portion which joins w/ duodenum |
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Term
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Definition
Greater curvature = lateral
Lesser curvature = medial |
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Term
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Definition
Greater Omentum - dorsal mesentery which connects the stomach to the posterior abdominal wall
Lesser Omentum - part of ventral mesentery that connects the stomach and the liver |
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Term
| Mucosa of the Stomach (Rugae + Gastric Pits) |
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Definition
Ridges in mucosa = RUGAE; disappear when stomach fills
Stomach mucosa is lined with simple columnar epithelium located in the gastric pits of the stomach; neck cells in gastric pits replace absorptive cells) |
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Term
| Mucosa of the Stomach (Gastric Glands) |
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Definition
Parietal Cells - large & round w/ a central nucleus; secrete HCl and intrinsic factor (for vitamin B12 uptake)
Chief Cells - cuboidal cells with basal nucleus; secrete pepsinogen (pepsinogen becomes pepsin due to acidity of HCl)
Enteroendocrine Cells (G cells) - secrete gastrin (gastrin stimulates parietal and chief cells) |
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Term
| Muscularis Externa of the Stomach |
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Definition
3 layers of smooth muscle in the stomach (aid in mixing of stomach contents):
Inner oblique layer
Middle circular layer
Outer longitudinal layer
At pyloric sphincter, middle circular layer thickens to form sphincter |
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Term
| Which layers of the GI wall does the stomach possess (histology) |
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Definition
| Mucosa, Submucosa, Muscularis Externa, Serosa (stomach is intraperitoneal) |
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Term
| Blood Supply / Drainage of the Stomach |
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Definition
The stomach is supplied by the 3 branches of the celiac trunk - splenic, L gastric, common hepatic
Corresponding veins responsible for drainage into PORTAL VEIN |
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Term
| Parts of the Small Intestine |
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Definition
| Duodenum (proximal), Jejunum (middle), Ileum (distal) |
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Term
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Definition
Proximal region of small intestine; connects to pylorus of stomach at pyloric sphincter; shortest portion = 25 cm
Receives common bile duct and pancreatic duct at duodenal ampulla, which empties into the duodenal papilla
Duodenum is RETROPERITONEAL |
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Term
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Definition
| J = 2.5 m; I = 3.5 m; both are covered by a fan-shaped mesentery, and are therefore INTRAPERITONEAL -> dorsal mesentery (mesentery proper) suspends jejunum and ileum to the posterior abdominal wall |
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Term
| Blood Supply / Drainage of the Small Intestine |
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Definition
Receives blood from the superior mesenteric artery (branch from abdominal aorta)
Blood drains into superior mesenteric veins, which connect to the hepatic portal vein |
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Term
| Mucosa of the Small Intestine |
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Definition
Plicae Circularis - permanent transverse folds in mucosa
Villi - finger-like projections of mucosa of the small intestine; covered with microvilli (brush border) to further increase the surface area
Villi are lined with absorptive cells (simple columnar epithelium) lined with microvilli
Crypts of Lieberkuhn - deep projections in between villi
Lamina Propria - forms a CORE for each villus, containing its blood supply; blood capillaries and lymphatic capillaries (lacteals; for fat digestion)
In jejunum - isolated lymphatic nodules in lamina propria
In ileum - aggregated lymphatic nodules (Peyer's Patches) |
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Term
| Crypts of Lieberkuhn (Small Intestine) |
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Definition
Intestinal glands projecting deep into intestinal walls located in between villi
Contain absorptive & goblet cells (like villi)
Paneth Cells - at base of crypt; secrete lysozyme (anti-bacterial)
Enteroendocrine Cells - @ base; secrete secretin & CCK (control gallbladder and pancreatic secretions)
Stem Cells - continuous regeneration of cells |
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Term
| Submucosa of Small Intestine |
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Definition
| In duodenum, contains duodenal (Brunner's) glands that secrete alkaline mucous; protective measures against acidic stomach contents |
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Term
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Definition
| Projection of the ileum; most common congenital anomaly of the small intestine; 2% of population have it; 2 " long; basically looks like "appendix" on ileum |
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Term
| Regions of the Large Intestine |
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Definition
3 main regions - Cecum, Colon (Ascending, Transverse, Descending, Sigmoid), Rectum
Total large intestine = 1.5 m long |
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Term
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Definition
Connects w/ ileum @ ileocecal valve
Vermiform Appendix - projection from cecum; contains many lymph nodules in wall; can be retrocecal (behind cecum) or pelvic (in pelvis) |
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Term
| Distinctive Features of Colon |
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Definition
Teniae Coli - 3 bands of longitudinal muscle
Haustra - "saculations"; gives colon segmented appearance
Epiplotic Appendages - sacs of fat in peritoneum |
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Term
| What is the main function of the large intestine? |
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Definition
| Reabsorb water and electrolytes from feces |
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Term
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Definition
From cecum -> upper R section of abdominal cavity; RETROPERITONEAL
Turns @ R colic (hepatic) flexure |
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Term
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Definition
Runs transversely from liver to spleen
INTRAPERITONEAL - suspended by transverse mesocolon
Turns to become descending colon @ L colic (splenic) flexure |
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Term
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Definition
| Travels downwards along the L side of the abdominal cavity; RETROPERITONEAL |
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Term
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Definition
| Terminal portion of colon; INTRAPERITONEAL -> suspended by sigmoid mesocolon |
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Term
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Definition
Storage area for feces; S-shaped in humans with 3 transverse rectal folds (aid in storage of feces)
Terminal portion = anal canal; anal columns are connected at the pectinate line by anal valves
2 sphincters (internal, external) |
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Term
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Definition
Internal - thickened circular layer of muscularis externa (smooth muscle)
External - skeletal muscle (voluntary) |
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Term
| Blood Supply / Drainage of the Large Intestine |
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Definition
Superior Mesenteric Artery = Cecum, Ascending and Transverse Colon (R side of large intestine)
Inferior Mesenteric Artery = Descending & Sigmoid Colon, Rectum (L side of large intestine)
Corresponding veins drain venous blood into hepatic portal vein |
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Term
| Mucosa of the Large Intestine |
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Definition
NO plicae or villi (smoother walls)
Simple columnar epithelium (same epithelium as small intestine)
Goblet cells increase in density heading towards the rectum (as feces dries, need more mucous to propel)
Epithelium in anal canal = stratified squamous epithelium
Crypts of Lieberkuhn (intestinal crypts) are deeper in the large intestine |
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Term
| Muscularis Externa of the Large Intestine |
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Definition
Cecum & Colon -> outer longitudinal muscle layer is in 3 distinct bands (teniae coli)
Rectum -> internal anal sphincter is a thickening of the inner circular layer of smooth muscle |
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Term
| Which sections of the colon are intraperitoneal? Retroperitoneal? |
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Definition
Intraperitoneal = Transverse, Sigmoid
Retroperitoneal = Ascending, Descending |
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Term
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Definition
Largest internal organ; 1.5 kg on average; located on R side of body
INTRAPERITONEAL (falciform & coronary ligaments; lesser omentum)
Filters venous blood via hepatic portal system; involved in the production of bile |
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Term
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Definition
Diaphragmatic = anterior, superior surface
Visceral = posterior, inferior surface |
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Term
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Definition
Separated into R and L lobes by the Falciform Ligament
Caudate Lobe - anterior; superior to quadrate
Quadrate Lobe - posterior; in between gallbladder and L lobe
Caudate & Quadrate lobes are both on visceral surface |
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Term
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Definition
Mesentery (formerly ventral) that separates the R and L lobes of the liver
Round Ligament - thickening of the ligament, showing where the umbilical vein existed |
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Term
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Definition
Mesentery that connects the liver to the diaphragm anteriorly
Bare Area - area of liver in direct contact with diaphragm (no mesentery) |
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Term
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Definition
| Connects the liver to the stomach |
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Term
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Definition
| The hilum of the liver; contains the hepatic triad - hepatic artery proper, hepatic portal vein, bile duct |
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Term
| What vessel brings the majority of the blood to the liver? |
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Definition
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Term
| What is the functional unit of the liver? |
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Definition
| The liver lobule (lobules separated by CT); consists of hepatocytes running outwards in cords from the central vein; sinusoids run in between adjacent cords |
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Term
| Where does the hepatic triad exist in relation to the liver lobule? |
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Definition
| Exists on the periphery of the lobule; blood from the artery proper and portal vein enters sinusoids at peripheries and travels towards central vein |
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Term
| Where do the nutrients filtered out of the sinusoids go? |
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Definition
| They enter the perisinusoidal space; here, they are absorbed by the microvilli of the hepatocytes |
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Term
| Path of blood entering and leaving the liver lobules |
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Definition
Blood enters lobule @ periphery from the hepatic triad (artery and portal vein); blood is absorbed into sinusoids and travels towards central vein; along the way, nutrients are transported into the perisinusoidal space where they can be absorbed by the microvilli of the hepatocytes
Remaining blood in sinusoids drains into the central vein where it is taken to the hepatic veins which connect to the IVC |
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Term
| Hepatocytes involvement in bile production |
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Definition
| Hepatocytes are also responsible for producing bile; bile is secreted into canaliculi which connect to the bile duct system |
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Term
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Definition
| Phagocytes located in the walls of the sinusoids which remove foreign pathogens & debris from the blood |
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Term
| What surface of the liver is the gall bladder associated with? |
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Definition
| Connected to the anterior surface of the liver |
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Term
| Path of bile leaving the liver lobules |
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Definition
Bile is secreted by hepatocytes into canaliculi which drain into the L and R hepatic ducts; these ducts merge to form the common hepatic duct
Common hepatic duct bile has two options:
- Continue to the common bile duct to empty into duodenum
- Continue to the cystic duct and drain into gallbladder for storage & concentration |
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Term
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Definition
Functions to store excess bile and concentrate stored bile
Small pear shaped muscular sac
Cystic duct connects gallbladder to the common hepatic duct/common bile duct |
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Term
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Definition
Serves as a conduit for bile from the common hepatic duct to the gallbladder
2-way duct - bile can travel to and from the gall bladder via the cystic duct |
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Term
| Blood Supply to the Gallbladder |
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Definition
| Supplied by the cystic artery |
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Term
| Regions of the Gall Bladder |
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Definition
Fundus - region that pokes out from under the liver
Body - main portion
Neck - junction w/ cystic duct |
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Term
| What is responsible for controlling secretion of bile from the gallbladder? |
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Definition
| CCK secreted by enteroendocrine cells of the crypts of Lieberkuhn in the small intestine |
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Term
| What does the secretion of bile aid in? |
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Definition
| Secretion of bile aids in the digestion of fats |
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Term
| Hepatopancreatic Sphincter (of Oddi) |
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Definition
| Closes off common bile duct before duodenal ampulla; release of CCK relaxes sphincter so bile can flow in (along w/ pancreatic juice) |
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Term
| Where does the common bile duct join with the pancreatic duct? |
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Definition
| At the duodenal ampulla; then bile and pancreatic juice enter the small intestine at the duodenal papilla |
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Term
| What gives bile its green-yellow colour? |
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Definition
| Bilirubin - byproduct of Hb degradation |
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Term
| What type of epithelium lines the gallbladder? |
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Definition
| Simple columnar epithelium w/ microvilli (similar to epithelium of the small and large intestines) |
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Term
| Histology of the Gall Bladder |
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Definition
NO muscularis mucosa; little submucosa
Muscularis externa consists of scattered muscle fibers
Outer adventitia (NO serosa) |
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Term
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Definition
Formed by the calcification and precipitation of bile
Typically get stuck in the neck of the gallbladder; more harmful if stuck in common bile duct |
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Term
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Definition
| RETROPERITONEAL; head located next to duodenum; tail located next to spleen |
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Term
| Pancreatic Duct (of Wirsung) |
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Definition
Joins w/ the common bile duct @ duodenal ampulla
Travels through the entire pancreas |
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Term
| Blood Supply / Drainage of the Pancreas |
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Definition
Head = supplied by the celiac and superior mesenteric arteries
Tail & Body = supplied by the splenic artery
Drainage to hepatic portal is by equivalent veins for each |
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Term
| Exocrine Histology of the Pancreas |
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Definition
Functional unit = acinus
The acini empty secretions into small ducts which drain into pancreatic duct of Wirsung
Secretes - enzymes for digestion, bicarbonate ions; creates an alkaline pancreatic juice to buffer and neutralize acids from the stomach |
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Term
| Pancreatic secretions are regulated by? |
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Definition
| CCK and secretin secreted by enteroendocrine cells of the small intestine glands |
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Term
| Where are the taste buds specific for "umami" found? |
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Definition
| In the circumvallate papillae |
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Term
| Which salivary glands are the largest by size? |
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Definition
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Term
| Which salivary glands produce the most saliva, on a daily basis? |
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Definition
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Term
| The greater omentum is connected to which curvature of the stomach? |
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Definition
| Connected to the greater curvature (lateral); greater omentum is the dorsal mesentery which secures the stomach to the posterior abdominal wall |
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Term
| Which nerve plexuses mainly control the contraction of the muscles of the small intestine? |
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Definition
| Myenteric (Auerbach's) plexus and submucosal (Meissner's) plexus |
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Term
| What is the transition of epithelium in the rectum? |
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Definition
Proximal rectum = simple columnar
Distal rectum = stratified squamous |
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Term
| What are the cartilages that make up the body of the larynx made of? |
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Definition
Cricoid & Thyroid = hyaline cartilage
Epiglottis = elastic cartilage |
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Term
| What is the epithelium of terminal and respiratory bronchioles? |
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Definition
| Simple cuboidal (non-ciliated) |
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Term
| Which T cell is known for direct cell mediated immunity? |
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Definition
| Cytotoxic T cells, as these cells directly attack foreign pathogens |
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Term
| What is the structural framework of red pulp? |
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Definition
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Term
| What type of capillaries exist in the spleen? |
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Definition
Sinusoids.
Filtered blood collects into sinusoids, which drain into trabecular veins which empty at the hilus of the spleen |
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Term
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Definition
| Exist in submucosa of duodenum and secrete an alkaline mucous to neutralize acidic contents of the stomach |
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