Alimentary

Question 1

what type of epithelium does the masticatory mucosa have?

Answer 1

keratinised or sometimes parakeratinised stratified squamous epi

Question 2

what is the term used to characterise nuclei in parakeratinised masticatory mucosa?

Answer 2

nuclei are pyknotic , aka highly condensed.

Question 3

epithelium of lining mucosa?

Answer 3

non-keratinised stratified squamous

Question 4

what type of mucosa covers the tounge?

Answer 4

specialised mucosa that contains lingual papillae

Question 5

which types of lingual papillae contain taste buds?

Answer 5

fungiform, circumvalate, foliate

NOT filiform

Question 6

what is the origin of enamel?

Answer 6

forms from epithelial cells called ameloblasts

Question 7

where does dentin. come from

Answer 7

secreted by odontoblasts (columnar epi cells)

Question 8

origin of salivary glands?

Answer 8

oral cavity epithelium

Question 9

epithelium of oesophagus?

Answer 9

non-keratinised stratified squamous

Question 10

what is the pattern of muscularis externa in upper middle and lower levels of oesophagus?

Answer 10

upper is striated, mixed in middle and smooth in lower 1/3.

Question 11

what epithelium lines the stomach?

Answer 11

simple columnar

Question 12

how does the lamina propria change in oesophogastric junction?

Answer 12

from loose CT to glandular CT

Question 13

what are the cavities called in epi of stomach?

Answer 13

gastric pits that go till muscularis mucosa

Question 14

what are rugae in stomach made out of?

Answer 14

submucosal folds

Question 15

where are mamillated areas located?

Answer 15

stomach, for increase in SA for secretion

Question 16

where are prietal cells located, what do they secrete and their nucleus location?

Answer 16

in stomach (neck region and upper parts of gastric pits) and secrete HCL and intrinsic factor (glycoprotein that complexes with VB12, centrally located nucleus

Question 17

what do chief cells secrete and their nucleus location?

Answer 17

pepsinogen into stomach that converts to pepsin used to break down proteins-basal nucleus

Question 18

what do enteroendocrine cells produce?

Answer 18

hormones e.g. gastrin

Question 19

what is special about enteroendocrine cells’ secretions?

Answer 19

their secretions do not go to gastric pits, they go to LP and enter BV, OR act locally.

Question 20

why are chief cells basophilic basally but eosinophilic in their cyto?

Answer 20

because of lots of rER below nucleus, but lots of zymogen granules in cyto

Question 21

what are mucous neck cells?

Answer 21

these are STEM cells that give rise to surface mucous cells if they migrate up.
if they migrate down, they differentiate into parietal, chief and enteroendocrine cells.

Question 22

how can we differentiate different regions in the stomach?

Answer 22

by cell types in glands

and depth of gastric pits.

Question 23

what is the key gross characteristic of small intestine mucosa?

Answer 23

plicae circulares

Question 24

what is a lacteal and where are they usually located?

Answer 24

blind-ended lymphatic capillary in the lamina propria of the villus.

Question 25

where are paneth cells located and what do they produce?

Answer 25

in small intestine (base of glands) which contain refractile secretory granules containing bacterial lysozymes

Question 26

enterocytes have a ..... located nucleus.

Answer 26

basally

Question 27

what is the core of a microvillus and what is the significance of it?

Answer 27

actin microfillaments that insert into terminal web. upon contraction of the terminal web the microfilamets allow spread of microvilli to increase SA for absorption

Question 28

where are lipid droplets in small intestine located?

Answer 28

in vesicles of sER, they migrate out of enterocytes as chylomicrons to lacteals.

Question 29

features special for duodenum?

Answer 29

brunners glands in submucosa that drain their alkaline secretions into base of crypts of Lieberkuhn

Question 30

what part of small intestine is the principal site of absorption

Answer 30

jejunum

Question 31

what is the key feature of ileum?

Answer 31

peyers patches located in lamina propria of villi

Question 32

what organ does coeliac affect, and what does it cause?

Answer 32

small intestine epithelium, the villus undergoes atrophy and become flat, crypt hyperplasia which causes elongation of them, increase in intraepithelial lymphocytes

Question 33

what are the key characteristics of large intestine?

Answer 33

no villi/plicae circulares, still have crypts of lieberkuhn, same epithelium cell types except paneth cells, numerous goblet cells, very thick muscularis externa. teniae coli

Question 34

primary exocrine function of liver?

Answer 34

bile production

Question 35

endocrine function of liver?

Answer 35

modifies structure and function of hormones e.g. thyroxine

Question 36

where are portal triads located?

Answer 36

intra-lobularly

Question 37

how is the flow of blood and bile in the liver classified?

Answer 37

blood is centripetal-towards central vein | bile is centrifugal-from hepatocytes towards portal triad into bile duct

Question 38

what lines the hepatic sinusoids?

Answer 38

1. fenestrated endothelial cells---have a discontinuous basal lamina 2. kupffer cells

Question 39

where does central vein drain into?

Answer 39

sublobular vein which converge to form hepatic vein==>IVC

Question 40

what is the path of plasma in liver?

Answer 40

plasma left in perisinusoidal space==> periportal space/space of mall

Question 41

how is bile transported from hepatocytes around liver?

Answer 41

through bile canaliculi which are sealed by zonulae occludens to prevent leakage

Question 42

function of hepatic stellate cells?

Answer 42

store vitamin A in lipid droplets==> to retina==>forms rhodopsin Also contributes to ECM remodelling post-trauma

Question 43

location of stellate cells?

Answer 43

liver perisinusoidal space/disse

Question 44

what type of cell lines the biliary tree?

Answer 44

cholangiocytes (cuboidal cells)

Question 45

pathway of bile ?

Answer 45

canaliculi==> intrahepatic ductules aka canals of Hering(lined with cholangiocytes)==>interlobular ducts at portal triad

Question 46

what controles bile secretion from gall bladder?

Answer 46

hormonal control of enteroendocrine cells cause smooth muscle contraction

Question 47

what type of epithelium does gallbladder have?

Answer 47

simple columnar with microvilli -no muscularis mucosa and no submucosa

Question 48

what are Rokitansky-Aschoff sinuses?

Answer 48

formed by mucosa folds when gallbladder is empty- normally prone to inflammation and precursor of gallstones.

Question 49

describe the appearance of acinar cells of pancreas?

Answer 49

basophilic cyto at base of cell and many zymogen granules in apical part (acidophilia). The acini are composed of simple epithelium serous cells

Question 50

pathway of acinar cells products in pancreas?

Answer 50

interclated ducts (centroacinar cells)==> adds bicarbonate and water==> intra-lobular (non-striated)==> interlobular (columnar) duct

Question 51

main type of cells in endo pancreas? and their function?

Answer 51

islets of langerhan They contain alpha cells: glucagon. beta cells: insulin delta cells: somatostatin