Histo Test 1 Stuff Flashcards
What 4 layers does the enamel organ differentiate into?
1) Inner enamel epithelium
2) Stratum intermedium
3) Stellate reticulum
4) Outer enamel epithelium
Which cells produce enamel?
Ameloblasts
Which layer induces formation of ameloblasts? From which layer do ameloblasts arise?
Induced by stratum intermedium; arise from inner enamel epithelium
What two things does the dental papilla differentiate into?
1) pulp cavity
2) Odontoblasts
What do odontoblasts secrete?
Dentin
Which cells or layer induces formation of odontoblasts?
Ameloblasts
What two main germinal layers are involved in tooth formation?
Oral epithelium and mesenchyme
The periodontal ligament anchors what together?
the bone of mandible and cementum covering dentin
Two cell types of cementum? Their functions?
1) Cementocytes–maintain cementum
2) Cementoblasts–secrete cementum
What makes up a cutaneous mucous membrane
Stratified squamous epithelium with supporting DICT
What type of connective tissue makes up the periodontal ligament?
collagen-type I
How many sets of capillaries does the portal system cross before reaching hepatic vein?
2 (GI capillary and sinusoids of liver)
The breakdown of what molecule creates bilirubin?
Hemoglobin
What molecule transports bilirubin to liver?
Albumin
What 3 structures are found in the portal area?
hepatic artery, portal vein, bile ducts
Macrophages of the liver
Kupffer Cells
Where does the plasma filter to from the sinusoids?
Space of disse
What makes bile?
Hepatocytes
What are the 3 liver lobule concepts?
1) Classic lobule
2) Hepatic acinus
3) Portal Lobule
What germ layer does the pancreas develop from?
Endoderm
What constitutes exocrine pancreas?
acinus and duct system
What constitutes endocrine pancreas?
Pancreatic islets
Which cell can be found in the lumen of acinus? What does it make?
Centroacinar cell; water and bicarbonate
Cells of pancreatic islets? What they secrete?
1) Alpha–glucagon
2) Beta–insulin
3) Delta– somatostatin
What do fat products in SI stimulate secretion of?
CCK
Actions of CCK
simulates acinar cells to secrete digestive enzymes & causes gallbladder contraction
What does acid in proximal SI stimulate secretion of? From what cells?
Secretin from “s” cells
Actions of secretin
stimulates water and bicarb secretion from centroacinar cells and intercalated ducts
What does stomach distension cause secretion of?
Gastrin
3 main classifications of hormones
1) Proteins and polypeptides
2) Amino-acid derivatives
3) Steroids and fatty acids
Where are peptide hormones stored? how do they circulate?
Cytoplasmic granules; unbound
What are amino acid hormones synthesized from? How do they ciruculate?
Tyrosine; unbound
Where are steroid hormones synthesized? Are they stored? How do they circulate?
mitochondria and SER; NOT STORED (made when needed; bound to plasma proteins
Major DIVISIONS of pituitary
Adenohypophysis and Neurohypohysis
Subdivisions of Adenohypophysis
Pars distalis
Pars intermedia
Pars tuberalis
Subdivisions of neurohypophysis
Pars nervosa
Infundibulum
Median eminence
Main nuclei and hormones of neurohypophysis
PVN and SON; vasopressin and oxytocin
Main cell type of pars nervosa
pituicytes
What structures in pars nervosa hold oxytocin and ADH
herring bodies
Main product of follicular cells? Stimulus?
T3 and T4; stimulated by TSH
Function of parafollicular cells
make calcitonin–lowers Ca concentration
Main product of colloid
Thyroglobulin
Major functional cell of parathyroid gland? Function?
Cheif cells–secrete parathyroid hormone (PTH) to increase blood calcium
3 layers of adrenal cortex (superficial to deep)
Zona glomerulosa, zona fasiculata, zona reticularis (GFR)
Zona Glomerulosa: stimulus? Class of hormones it secretes? Example?
Angiotensin II, ACTH
Mineralocorticoids
ex: aldosterone
Zona fasiculata: stimulus? main cell type? class of hormone it releases? Example.
ACTH
Spongiocytes
Glucocorticoids
Cortisol
Zona reticularis: stimulus? releases was classes of hormones?
ACTH
glucocorticoids and androgens
What germ layer gives rise to cortex? Medulla?
Cortex: mesoderm
Medulla: ectoderm
Cell type of medulla? what do they make and release? Stimulus?
Chromaffin cells
Epi and NE
preganglionic splanchnic nerves
Tongue papillae are modifications of what layer(s)?
mucosa
5 types of papillae
conical, filiform, fungiform, vallate, foliate, vallate
Which taste bud cell type can regenerate (name and #)
Type IV–Basal cells
Site of transition between epidermis and mucous membrane
Mucocutaneous junction
What’s the layer under epithelium when m. mucosae if absent?
lamina propria-submucosa (grouped)
Location of seromucous gland in esophagus? how are dogs different?
in submucosa; all have them in just cranial portion; dogs have them throughout
Muscle composition of esophagus in
1) dogs/ruminants
2) cats/horses
3) humans/pigs
1) all skeletal
2) upper 2/3 skeletal; lower 1/3 smooth
3) skeletal upper, mixed middle, lower smooth
Which esophagus portions have adventitia? serosa?
cervical portion–adventitia
thoracic and abdominal–serosa
Which section of ruminant stomach lack a muscularis mucoase?
Rumen
Which section of ruminant stomach has a honeycomb appearance
Reticulum
Which section of ruminant stomach has m. mucosae in apex of crests
reticulum
What makes up the trilaminar appearance of omasum?
complete m. mucosa with inner circular m. externa between
What are the projections in omasum called?
laminae
Layers of m. externa in glandular stomach?
inner oblique, middle circular, outer longitudinal
Function of epidermal growth factor on parietal cells
inhibits HCl production
Which layer of m. externa can form thickened areas called ______?
outer longitudinal can form taenia coli
constriction of taenia coli causes?
haustra coli
