Lab Part II Flashcards
Which layer(s) of the heart are highlighted? What special structures are included?
Endocardium (epithelium+CT) and subendocardium (btwn endocardium and myocardium); subendo. much thicker here to contain Purkinje fibers
What is the large structure here? Which cardiac layer is it part of?
Major cardiac vessel (filled w/ resin) in subepicardium (adipose + CT)
Name the layers here
Tunica intima (endothelium
Tunica media (elastic lamellae)
Tunica adventitia (external CT)
What are the white squiggles on the inside and outside of the vessel?
Internal + external elastic laminae (muscular arteries)
What are these highlighted vessels within the vessel structure?
Vasa vasorum; vessels that supply outer walls of large vessels. Not pictured: nervi vasorum
Which 2 lumens are here?
Trachea below, elastic artery above. Notice cartilage w/ trachea
Which epithelial cells are distinguishable here?
- Ciliated cells (most of them)
- Mucous cells
- Basal stem cells (small, squished by basement membrane)
Notable layers and structures here
- Pseudostratified tracheal epithelium
- Thick tracheal basement membrane
- Lighter lamina propria
- Darker submucosa
- Tracheal submucosal glands
How can you determine that this is the trachea?
C-shaped cartilage rings, pseudostratified epithelium
What is this accumulation of cells?
Bronchial Associated Lymphoid Tissue (by the trachea)
Which structure is circled?
Intrapulmonary bronchus
Notice it’s in the lung tissue and has cartilage plates
What is the progression of highlighted structures here?
Terminal bronchiole (only club cells)
Transition to alveolar epithelium
Alveolar duct connecting several alveolar sacs which have several alveoli
What is this highlighted layer?
Visceral pleura (serous membrane, mesothelium + CT)
What are the highlighted cells?
Top to bottom: alveolar macrophage (smooth here bc germ-free mouse), AT2 cell (lamellar bodies w/ surfactant), RBCs in alveolar capillaries (surrounded by AT1 cells and aerocytes)
How do you differentiate between AT1s, aerocytes, and gCap cells?
AT1 nuclei will poke into the alveolar epithelium, endothelial cell epithelia poke into the capillary lumen. Aerocytes line capillaries in thin walls (and some thick), gCaps are in thick wall vessels only
Which lung pathology is depicted here?
Panacinar emphysema (all levels of lung), not centrilobular (only centers of lung lobules near respiratory airways. Alveoli wall collapse leads to much larger spaces within lungs; vs atelectasis = collapse of alveoli
Which lung pathology is depicted here?
Pulmonary fibrosis. Lots of scar tissue fibers invading/eliminating alveolar space, CT overgrowth, macrophage accumulations, lymphocyte infiltration, also much thicker visceral pleura serosal layer
What structures/cells are mainly shown here?
Thyroid follicular cells connected by tight junctions w/ colloid-filled lumen. Only endocrine cells w/ apical surface!
What are the stained granules? Where are they localized?
Intracellular thyroglobulin granules, contained in apical domain of thyroid follicular cells.
These thyroid follicular cells are more active compared to the other slide. How can you tell?
Primarily due to their more cuboidal shape (squamous = less active); also seen here from the granules being secreted
What are the darker staining cells highlighted here?
Parafollicular cells (C-cells) of thyroid follicle; secrete calcitonin and have a darker staining cytoplasm.
What are the major components of the pituitary?
Post. neurohypophysis (left):
- Pars nervosa
- Infundibular stalk
- Median eminence
Ant. adenohypophysis (right):
- Pars distalis
- Pars intermedia
- Pars tuberalis
To which cells do the nuclei here in the pars nervosa belong to? What is the circled structure/other structures similar to it?
The nuclei belong to pituicytes (resident glia); most everything else is neuropil. The circled structure is a Herring body; axon ending dilated with hormones to be released.
What are the different adenohypophysis cell types observed here? What do they secrete?
Acidophils (eosinophilic): GH, PRL
Basophils (a few): ACTH, FSH, LH, TSH, beta-endorphin
Chromophobes (highlighted): idk
RBCs (clear)
Given that this is PAS, what are the brightly staining cells in the adenohypophysis?
Basophils, whose hormones all have glycoprotein precursors which get stained by PAS. Notice how the basement membranes are also brightly stained, indicating PAS.
Which endocrine gland is this? How can you tell?
Pineal gland, notable by basophilic brain sand (corpora arenacea) accumulations.
What are the layers depicted here? What are their primary products?
Right to left:
Adrenal capsule
Adrenal cortex:
Zona glomerulosa (aldosterone)
Zona fasciculata (cortisol)
Zona reticularis (androgens)
Adrenal medulla (epi/NE)
What is this structure next to the adrenal gland? What type of structure is it?
Suprarenal vein next to adrenal glands; vena cava type vein (notice smooth muscle patches in the walls)
What causes the characteristic foamy appearance of the zona fasciculata?
Cholesterol droplets from steroid hormone production.
What are the major vasculature here?
Medullary veins
What is this structure running through the adrenal cortex here?
Long cortical artery
What gland is this? What are the primary cells shown?
Parathyroid gland. Mainly made of chief cells, minority oxyphils (eosinophilic clusters)
What are the main layers of a thymic lobule?
Outer thymic medulla, inner thymic medulla
What are the cells/highlighted structures found here in the inner thymic medulla?
Majority cell: thymocytes
Most eosinophilic cells: epithelioreticular cells
Structure: Hassall’s corpuscle (thymic corpuscle); layered ERCs
Eosinophilic cells w/ dark inclusions: thymic macrophages
What’s happened to the thymus here?
Involution with adipocytes; occurs normally in thymus with age.
Which component of the liver portal triad is highlighted here?
Bile duct; notice active columnar/cuboidal cells
What hepatic subdivision is outlined here?
Hepatic acinus; diamond w/ 2 opposing central veins, 2 opposing portal triads
What hepatic subdivision is outlined here?
Hepatic lobule; roughly hexagonal plate w/ portal triads at corners, central vein at center.
What hepatic subdivision is outlined here?
Portal lobule; triangle shape w/ central veins at corners, portal triad at center.
What cell type is highlighted here (liver)?
Kupffer cells aka resident macrophages with inclusions
What is the capsule layer called? What organ is the liver adventitial to (above)?
Glisson’s capsule, adventitial to gall bladder
What causes these white inclusions in hepatocytes?
Cholesterol (synthesized/bile production)
Which 2 morphological abnormalities are present in this case of alcoholic hepatitis?
Fibrosis and fatty deposits
What features mark the transition from oral epithelium to reticulated epithelium of the tonsils?
Basement membrane disappears, cell desmosomes disappear (no lighter rings around cells in reticulated epithel.), CT cells intruding into epithelium/lumen
What type of epithelium is found here in the pharyngeal tonsil? What is the circled cell?
Respiratory epithelium (pseudostratified, ciliated)
Circled cell is an intraepithelial lymphocyte
What structures are the reticular fibers outlining here?
Fibers encircle splenic sinuses and run perpendicular to the long axis of endothelial cells; stave + hoops of a barrel model. Fiber circles where sinuses are transversely cut. Other spaces = splenic cords
What are the outlined CT structures here?
Splenic capsule, splenic trabeculae extending into red pulp
What are the highlighted structures here? What types of cells are found in different layers?
White pulp (splenic nodule) with mantle, germinal center, central arteries (contained within peri-arterial lymphatic sheath).
PALS = T cells
Follicle = B cells
Marginal zone = APCs
What vasculature is shown here?
Trabecular artery (notice dense CT surrounding it)
What are the regions of the lymph node medulla?
Medullary cords (CT) and medullary sinuses (spaces)
What is this lymph node structure and the space around it termed?
Trabecula and peritrabecular sinus (intermediate sinus)
What’s special about this venule in the lymph node?
Cuboidal, active endothelium due to lymphocyte diapedesis; High Endothelial Venule
Layers of the lymph node and distinguishing features
Capsule: CT covering
Cortex: lymphoid follicles
Paracortex: no lymphoid follicles, no medullary cords (mainly T cells)
Medulla: cords and sinuses, HEVs
What are the highlighted structures here?
Glomeruli in the kidney cortex
What are the different layers of the kidney here?
Cortex, medulla, minor calyx, major calyx, sinus (CT region), hilus
What is the small circled structure in the kidney sinus here?
Ureter
What is the outlined structure here? What area does it define in the kidney?
Medullary ray, radiating towards medullary pyramid. Comprised of collecting ducts, defines center of renal lobule
How many lobules are present here?
~4
What is this region? What is important about it?
Kidney hilus; point of entry/exit for renal arteries/veins/lymphatic vessels
What is the capillary bed in this region called?
Peritubular capillary plexus; capillary bed for renal cortex
What is the name of this artery?
Arcuate artery; enters at cortico-medullary border
What is the name of these vessels?
Arcuate artery/vein
What is this vessel?
Interlobar artery; in renal sinus, runs between lobes
What are the paired, circled vessels called?
Interlobular artery/vein; runs between lobules aka between medullary rays
What are the different structures at the end of the medullary pyramid?
- Minor calyx
- Vasa recta (medulla capillary supply)
- Ducts of Bellini/collecting ducts
- Thin tubules (smaller structures)
What is the highlighted section?
Urinary pole
Name the structures of the JGA
- Macula densa (part of distal tubule)
- Extraglomerular mesangial cells
- Not pictured: JGA cells w/ renin
What type of epithelium is this?
Urinary epithelium; lining minor calyx
This is a collecting duct. How can you tell?
A few very eosinophilic intercalated cells compared to the majority principal cells
Which tubule is which?
Top right = distal tubule
Below it = PCT
Notice shorter, smaller cells (more nuclei), in cortex less frequent vs PCT
What are the two highlighted structures?
Left: thick descending tubule (similar to PCT)
Right: thick ascending tubule (similar to DT)
What are the different layers of the renal corpuscle?
- Parietal layer of Bowman’s capsule
- Bowman’s (urinary) space
- Visceral layer of Bowman’s capsule (podocytes)
What are the different cells of the renal corpuscle?
- Simple epithelial (parietal layer)
- Podocytes w/ pedicels (visceral layer)
- Intraglomerular mesangial cells
- Extraglomerular mesangial cells (Lacis cells)
- Capillary endothelial cells (fenestrated capillaries)
What are the two types of ducts here in the parotid gland?
Smaller circled: intercalated duct
Larger structures: striated ducts
What are the structures at the edges of the gland?
Serous demilunes; mucous cells pushed to edges by prep due to serous cell expansion
What is the circled piece in the middle of the acinus here? Which organ are we in?
Centroacinar cell, part of intercalated duct in exocrine pancreas
What are the vessels here, top to bottom?
- Interlobar artery/vein
- Renal vein (left)
- Renal artery (right)
- Aorta
What are the two different ducts highlighted here?
Interlobar duct and interlobular duct (mammary glands)
Which stage in tooth development is shown here?
Dental lamina stage (invagination of oral ectoderm)
Which stage in tooth development is shown here?
Cap stage; enamel organ formed. Notice the degenerating dental lamina at the top of the organ
What are the different epithelia in the enamel organ?
- Oral epithelium
- Outer enamel epithelium
- Inner enamel epithelium
All epithelium derived
What is the circled area?
Stellate reticulum; GAG-filled space derived from ectoderm (EMT); supports shape of enamel organ through hydrostatic pressure
What are the cellular layers here in the inner enamel epithelium?
Towards stellate reticulum: stratum intermedium (tooth shape)
Outer: pre-ameloblasts
What is the area of condensing mesenchyme under the enamel organ?
Dental papilla
What is this stage in tooth development?
Bell stage; based on enamel epithelium shape
What is the circled area? What are the highlighted cells?
Circled: cervical loop
Cells: ameloblasts on inner enamel epithelium
Name the different cells/layers/structures here
Left to right:
- Ameloblasts (reversed polarity)
- Enamel (lost in prep)
- Dentin w/ dentinal tubules
- Pre-dentin secretion
- Odontoblasts
- Pulp cavity
What is the highlighted epithelium called?
Hertwig’s root sheath; inner enamel epithelium extending past cervical loop
What type of epithelium is this?
Masticatory oral epithelium, part of gingiva
What are the layers of cementum here?
Cellular + acellular cementum (lacunae)
What is the highlighted structure? What type of fibers does it contain?
Peridontal ligament connecting cementum to bone via Sharpey fibers
Notable esophageal structures
- Submucosal esophageal glands
- SSNK epithelium
- Mostly adventitial
What’s the highlighted structures?
Z-line/LES (physiological sphincter); transition between esophagus and cardiac stomach
