CTO Quiz 5 Flashcards
1
Q
What kind of epithelial cells line most of the oral cavity?
A
Non-keritanized stratified squamous epithelium
2
Q
What is the histologic structure of the tongue?
A
- Mostly skeletal muscle
- stratified squamous non-keritanized epithelium
- CT bands and minor salivary glands between bundles of skeletal muscle
- posterior 1/3 of tongue has lymphoid tissue under epithelium
3
Q
What kinds of papillae are on the tongue and what are their structures?
A
- Filiform Papillae are the most numerous (short bristles)
- Fungiform papillae are broader (have taste buds)
- Circumvallate form a row just anterior to the sulcus terminalis (lots of taste buds)
4
Q
What divides the anterior 2/3 of the tongue from the posterior 1/3?
A
The Sulcus Terminalis
5
Q
What kind of epithelium lines the pharynx?
A
The oro-laryngopharynx are lines by stratified non-keratinized squamous
- the nasopharynx = pseudostratified columnar with cilia
6
Q
What is the innermost lining of the GI tract and its layers?
A
The mucosa
- epithelium
- lamina propria
- muscularis mucosa
7
Q
What is the submucosa?
A
CT layer in between muscularis mucosa and muscularis externa
8
Q
What is the structure of the muscularis externa?
A
- inner circular layer
- outer longitudinal layer
- stomach may have an additional layer
- colon has extra layer (taeniae coli)
9
Q
What is the outer layer of the GI tract and what is its structure?
A
- CT layer
- when there is no mesentary = adventitia (blends with other CT around organ)
- when there is mesentary = serosa (added layer of simple squamous mesotheilal cells and underlying CT)
10
Q
What portions of the GI tract have stratified squamous epi?
A
- oral cavity
- pharynx
- esophogus
- anus
11
Q
What part of the GI tract have submucosal mucous glands?
A
- esophogus
- duodenum
12
Q
What is unusual about the muscularis externa of the esophagus?
A
It has skeletal muscle in proximal 1/3
smooth muscle in distal 1/3
blends in the middle
13
Q
What portion of the intestine doesn’t have villi?
A
Colon
14
Q
What kind of cell is found in the epithelium of the small and large intestine but lacking from the stomach?
A
goblet cells
15
Q
What do most of the surface epithelium in the stomach secrete?
A
sticky muscous, high pH, lots of bicarb
16
Q
What are the infolding of the stomach muscosa called?
A
Gastric pits increase surface area of the stomach and allow surface muscous cells to produce lots of alkaline mucous to protect the lining
17
Q
What cells of the gastric glands manufacture and secrete HCL? What is unusual about their structure? What else to they produce?
A
- Parietal (oxyntic cells).
- has canaliculi to increase SA
- secrete HCL, using carbonic anhydrase to make acid
- need pumps to move H+ ions (needs ATP, and lots of mitochondria)
- Also secrete intrinsic factor, for absorption of B12 from the ilieum
18
Q
What are the cells that make most of the gastric enzymes?
A
- Chief Cells
- produce pepsinogen, stored in zymogen granules
- basophilic basal end (RER)
- esinophilic apical end (vesicles)
19
Q
What is the function of the enteroendocrine cells in stomach?
A
Secrete Gastrin (stimulates acid production by parietal cells)
20
Q
Where are the stem cells of the gastric epithelium located
A
Near the neck of gastric glands and multiply to replace cell lining
21
Q
From large to small, what are the folds in the SI
A
- plicae circularis
- villi
- microvilli
22
Q
What forms the core of the intestinal villus?
A
The lamina propria (contains lymphatics, nerves, capillaries, smooth muscle, CT)
23
Q
Where in the GI tract would you find villi?
A
only in SI
24
Q
In what layer of the intestine would you find intestinal glands?
A
In the lamina propria (mucosa)
25
Where do you find stem cells in the intestines and how long does it take to replace intestinal lining?
- crypts of Lieberkhun
| - 3-6 days
26
Outside of enterocytes and globlet cells, what are other cells found in the epithelium of the intestinal glands?
- Paneth cells in the Crypts
27
What hormones are produced by cells of the duodenum?
- Cholecystoskinin (affects gall bladder)
| - Secretin (affects pancreas)
28
What are the submucosal glands of the duodenum called
- Brunners glands produce alkaline muscous to neutralize acid
29
Crypts of Lieberkuhn
- Extend from villi down into lamina propria
- has mitotic activity (stem cells)
- Has Paneth Cells (lysozyme to break down bacterial walls)
- in SI
30
What part of the intestine has the greatest surface area?
jejunum (long villi and plicae circularis)
31
What is the most obvious difference between the jejunum and the ileum?
Ileum has more lymphoid tissue (Peyer's patches) visible to eye
32
What kind of unique cells are located in the mucosa of the ileum?
M-cells sample antigens and present it to lymph tissue in the region of peyer's patches
33
What is uniquely absorbed from the ileum?
Absorbs bile acids & B12 (requires gastric intrinsic factor)
34
Where does most of the resorption of H20 and electrolytes take place?
Small itestine
35
What is unique about the muscularis externa of the colon?
The longitudinal layer of the muscularis externa has 3 bands
36
What are the most striking differences between the epithelial layer of the large and small intestine:
- more goblet and no villi
37
What is the most striking histologic feature of the appendix?
lots of lymphoid tissue with lymphoid follicles
38
What is the most striking difference between the rectum and the rest of the colon?
Rectum outer longitudinal layer of SM is circular/complete (opposed to semi-lunar)
39
Where do find ganglion cells in the GI tract?
The ganglion cells (with which parasympathetic preganglionic nerve fibers synapse) are found in
1. Meissner's plexus (in the submucosa)
2. Auerbach's plexus (between layers of muscularis externa)
40
What kinds of glands are the salivary glands?
- Compound tubuloalveolar glands
- Parotid = serous
- Submandibular = mixed
- Sublingual = mucous
41
What kind of cells are located between gland cells and basement membrane to aid in movement of secretions out of the acini?
Myoepithelium
42
What ducts are present in the oral cavity of the salivary glands?
Intralobular:
1) Intercalated (low cuboidal epithelium, close to acini)
2) Striated (high cuboidal epi, lots of mitochondria, involved in ion transport, and secrete lysozyme and transport IgA antibody)
Interlobular:
- between lobules, found in CT
- large, stratified columnar
43
What is the structure of a pancreatic acinus?
- exocrine
- entirely serous
- produce proenzymes that will be activated in the duodenum
- look similar to salivary glands
- NO striated ducts
- NO myoepithelal
- HAS CENTROACINAR
- flud part is alkaline = bicarb
44
What are the functions of the liver?
1. Produced bile
2. detoxifies blood
3. protein synthesis (clotting factors and plasma proteins like albumin)
4. storage of lipids and glycogen
5. Gluconeogenisis
45
What is the lining of the liver sinusoids?
discontinuous and fenestrated
| for easy exchange of substances with the space of Disse
46
What are Kupffer cells?
- resident macrophage in sinusoidal space
47
What is the space of Disse?
- Perivascular space
- in between sinusoid and hepatocytes
- has reticular fibers
- has ITO cells for Vit A storage
48
What is the apical portion of the hepatocyte?
forms the wall of the bile canaliculus (there are tight junctions that separate the apical domain of the hepatocyte from the lateral portion that borders the adjacent hepatocytes)
49
What is the epithelium of the gall bladder?
Simple columnar with microvilli
50
What is the epithelial lining of the bile duct?
simple cuboidal
51
What are the differences between the wall of small intestine and that of the gallbladder?
- no goblet cells
- large lamina propria
- no submucosa and no muscularis mucosa
- There are mucosal folds but not villi
- muscularis externa is not regularly arranged
52
What is the function of the gall bladder?
Stores and concentrates bile:
- removes Na and Cl, H20 follows passively
- these are pumped from the lateral aspects of the cells, where they enter into the intercellular space
53
Pituicytes
Supporting cells of the posterior pituitary gland
54
Herring bodies
granular stores of NT within axons of posterior pituitary
55
What are the functions of the endocrine system?
- regulation of growth
- reproduction
- metabolism
- fluid levels
- glandular secretion
56
How does the hypothalymus affect the endocrine system?
- site of release of the releasing and inhibiting factors that enter the hypothalamo-hypopheseal portal system
- affects anterior and posterior pituitary secretions
- also site of manufacture of oxytocin (paraventricular nucleus) and vasopressin (supraoptic nucleus) and send them to the post. pit.
57
What is the "master gland" of the body?
Pituitary gland controls many other endocrine glands
58
What are the functions oxytocin?
- Acts on uterine smooth muscle during labor as part of positive feedback loop
- it contracts myoepithelial cells of mammary alveoli for milk letdown
- this may be stimulated by suckling or by psychological factors such as a baby crying
59
What is the embryologic origin of Adenohyophysis?
- Rathke's Pouch (roof of oral cavity.. ectoderm)
60
What is the capillary organization of the anterior pituitary?
Hypothalemo-hypophyseal protal system that takes releasing factors from the median eminence of the hypothalamus to the anterior pit.
- has many fenestrated capillaries and no barrier (no BBB)
61
What do the acidophils of the adenohypophysis secrete?
Secrete NON-TROPIC hormones (growth hormone and prolactin) --> direct effect
62
What does growth hormone do?
- Is produced by somatotropes (under influence of GRH)
- stimulates synthesis of GH
- increases cell division
- inc protein synthesis
- inc fat breakdown
- regulate blood sugar (high blood sugar via glycogen breakdown)
- somatostatin = growth hormone inhibiting factor
63
What is prolactin?
- promotes milk production
- produced by lactotrophs
- inhibited by dopamine
- released into the HH portal system
- suckling reduces this inhibition
64
What do basophils in the ant. pit. do?
Secrete TROPIC hormones:
- ACTH (corticotropes)
- TSH (thyrotropes)
- FSH/LH (gonadotropes)
65
What do chromophobes of the adenohypophysis do?
- not active in secreting hormones
| - resting or replacement cells
66
What does the thyroid gland control?
- temperature control
- basal metabolic rate
- growth
- nervous development
67
Describe the histologic appearance of the thyroid?
- Large follicles lined by cuboidal follicular cells
- there is colloid within follicles (more inactive glands) and there are parafollicular "c" cells between follicles
- many capillaries
68
What is colloid?
Made of protein thyroglobulin
- this is secreted into follicle colloid by follicular cells
- These cells take up iodine and pump it into colloid where it iodinates thryoglobulin to make T3 and T4
69
How is thryoid hormone secreted?
- stimulated by TSH
- follicular cells reuptake thyroglobulin and liberate T3 and T4
- secreted into blood stream
70
What is the significance of resorption lacunae?
- regions near the active follicular cells where processes of these cells have internalized thyroglobulin
- leaving and empty appearing region adjacent to the cell
- more prominent in active thyroid
71
Why is calcium regulation important?
- too little = muscle cramps and tetany (hypocalicima)
| - too much = muscle weakness, confusion, fatigue (hypercalicemia)
72
What kind of cells are there in the PT gland?
- chief cells (secrete parathyroid hormone)
| - Oxyphil cells are more eosinophilic due to more mitochondria (no known function)
73
What does PT hormone do?
- increase Ca2+ in blood
- increase osteoclast activity
- inc Ca2+ resabsorption in kidney and GI (by activating vit D)
74
What are the layers of the Adrenal Cortex?
- Glomerulosa
- Fasciculata
- Reticularis
75
What does the zona glomerulosa do?
- secrete mineralcorticoids (adolsterone)
- under influence of RAAS system
- regulate electrolytes and water levels
76
What does the zona fasiculata do?
- secrete glucocorticoid (cortisol)
- hormone helps deal with stressful situation
- inc blood sugar, fat, amino acids, and BP
- has a circadian rhythm, being high in the morning
- regulated by ACTH from ant. pit
77
What does zona reticularis do?
- weak androgens
- responsible for testosterone in women
- makes estrogen in postmenopausal women
78
Where does the adrenal medulla arise from?
- neural crest cells
| - similar to sympathetic ganglion cells
79
What are the cells of the adrenal medulla and what do they do?
- Chromaffin cells
- innervated by sympathetic preganglionic neurons
- secrete epi and NE
- inc BP, HR, blood glucose
80
What is the endocrine portion of the pancreas called?
Islets of Langerhans
81
What type of cells are in the endocrine portion of the pancreas?
- B-cell: secrete insulin in response to high blood sugar
- a-cell: secrete glucagon in response to low blood sugar
- Delta cell: secrete somatostatin which inhibits local hormone production
- F cells: secrete pancreatic polypeptide
82
What are the cells of the pineal gland called and what are the distinctive histologic features?
- pinealocytes
| - corpora arenacea (mineral deposits that show up on CT/MRI - brain sand) - effective distinguishing feature
83
What does the pineal gland do?
Produces melatonin (helps sleep)
