Gastrointestinal Tract

Question 1

Pharynx (Function)

Answer 1

Carry food and air

Question 2

Pharynx (Composition)

Answer 2

Mostly Stratified squamous non keratinized. The resp area is pseudostratified rep epithelium

Question 3

three areas of the pharynx

Answer 3

nasopharynx - behind nasal cavity
orpharynx - behind the oral cavity
Layrngopharynx - behind larynx

Question 4

Canal General Organization

Answer 4

Mucosa - Lining Epithelium, lamina propria, muscluaris mucosase
Submucosa - Dense irregular usually has meisners plexus
Muscluaris Externa - inner circular and outer longitudinal with auerbachs plexus in between
Serosa or adventitia - seroa has underlying connective tissue and mesothelium
adventitia just connective tissue

Question 5

Esophagus ( special chracteristics of Layers)

Answer 5

Lining - stratifies squamous nonkeratinized
Lamina propria - see MALT, lymph nodules
also see esophageal cardiac glands distal in esophagus
musclaris mucosae not present in oral cavity
Submucosa - has manty elastic fibers and has esophageal glands proper
Muscularis externa slowly swtiches from skeltal to smooth (from upper 1/3 to lower
Thoracic - has adventitia
ABdmonial - serosa covers

Question 6

Esophogeal Cardiac Gands

Answer 6

Distal in esophagus in order to protect from fluids in reflux

Question 7

Esophageal Galnds proper

Answer 7

in the submucosa layer and they function to lube wall faciliateate food and keep moist

Question 8

Gastro esophogeal Junction

Answer 8

Abrupt change in epithelium from sratified squamous non keratinizedd to simple squamou to columnar

Question 9

Gastroesophogeal sphincter

Answer 9

physiologic sphincter that has increase in tone in the inner circular layer of mucslaris externa
not an increase in bulk so it not as effective as an anatomical sphincter and stuff can back up

Question 10

Stomach gross anatomy sections

Answer 10

Cardia - adjacent to espohagus near heart
Fundus - extend above where esophagus enters
Body - large main section
PYlorus is where stomach tapers

Question 11

3 histological regions

Answer 11

the body and fundus become the gastric section

Question 12

Rugae

Answer 12

transient folds in tstomach to increase surface area

Question 13

Layers of the stomach

Answer 13

lining epithelium - has simple columnar epithelium
lamina propria - surrounds gastric pits, MALT and lymph nodules
Muscularis Mucosa - normal for outflow
Submucosa - contains blood vessels. may see GALT
Muscluaris externa - has three layers with inner oblique middle circular and outer longtidudinal
Serosa - is covers entire stomach

Question 14

Gastric Pits

Answer 14

branching 3-7 projections in glands. They extend thorugh the lamina propria to the level of the muscularis mucosae

Question 15

Parts of the gastric pits

Answer 15

isthmus - the narrow passage where glands connect glands
Neck 0 the the branch point of pits
Base- the main tube of the gland

Question 16

6 Cell types of simple columnar lining epithelium

Answer 16

Surface Mucous 
Mucous Neck
Stem Cells 
Enteroendocrine Cells 
Pariatel Cells 
Chief Cells

Question 17

Surface Mucous Cells of Stomach

Answer 17

in luminal surface and gastric pits, have apical mucigen granules and basal nucleus
Function is to release mucin which mixes with water to form buffer blanket

Question 18

Mucous Neck Cell of Stomach

Answer 18

located in isthmus and neck of pitws in teh cardiac pyloric and gastric section of stomach
apical mucigen and basal nuclues. The funciton is same as surface mucous but its a different secretion

Question 19

Stem Cells of Stomach

Answer 19

location is in all parts of stomach

columnar, release reneweal of all stomach epithelial

Question 20

Enteroendocrine cells of stomach

Answer 20

at the base of pits in all cells
basally located secretory granules
function is to release hormones to blood

Question 21

Parietal Cells of stomach

Answer 21

location thorughout gastric pits and few in cardiac pits
large triangular shape with intracellular canaliculi and microvilli for surface area for pumps
very eosionpihillic because mitochondria
function is to pump h and cl seperately to make HCL

Question 22

cheif cells of stomach

Answer 22

location - base of gastric pits
structure - basophilic because of rough er
release apical granules of pepsinogen which convertes for digestion
also secrete gastric lipase

Question 23

what cells are in the what sections of the stomach

Answer 23

gastric (fundus and body) - has them all
cardiac - has all but chief and only some parieatal
Pyloric - has not parieetal or chief

Question 24

pyloric sphincter

Answer 24

between stomach and duadenum formed by thickening of muddle circular layer of muscluars externa. isssss a thickening not tone so anatomical sphincter

Question 25

Small Intestine regiosn

Answer 25

duadenum jejunum and ileum

Question 26

3 absorption featres of small intesting

Answer 26

villi - evaginations of mucosa along the circulares. lined with simple columnar with a lamina propria core wtih blood vessels plicae circulares - series of perminant cicular folds of mucosa snd submucosa Microvilli - located at apical aspect of enterocytes for increase contact

Question 27

LAyers of the small intestine

Answer 27

Lining Epithelium - 6 cell types all simple columnar have villi lamina propria - core of each villis surround crypts, contain fenestrated capillaries lactea smooth mucsle MALT and nodueles Muscularis mucosa - move villi Submucossa - has lymph vessels (See differences in each section) Musculares Externa - normal Serosa - covers majority Adventitia - where duadenum is in contact with abdominal wall

Question 28

Lieberkuhn

Answer 28

intestinal glands or crypts

Question 29

what are the six cell types in lining epithelium of small intestine

Answer 29

``` enterocytes, goblet cells enteroendocrine paneth cells M Cells Stem Cells ```

Question 30

Enterocytes of SI

Answer 30

absorption. line luminal surface of villi, mirgrate from crypt and mature Have mircrovvili covered in glycocalyx absorption - transprot nutrients to the circulation. Secrete glycoprotein alaso for digesion aslo secrete water for maintain chyme KNOW THE SECRETORY ROLE

Question 31

Goblet Cell of SI

Answer 31

``` location - ling lumen of villi and crypts among the enterocytes increase as go from duadenum Structure - goblet shape with apical accumulation of mucigen granules function - secrete granules mucin apical to combine with water to form mucous product to lube and protect ```

Question 32

enteroendocrine of SI

Answer 32

scatters al over. Basal secretory granules release hormones to blood

Question 33

Paneth Cells of SI

Answer 33

base of crypt only in small intesting apical eosinophilic granules, Function - have lysozyme to digest cell wall of bacteria

Question 34

M Cells of SI

Answer 34

over large lymph nodules Structure - apical microfolds, and basal intracellular pockets immune cells migrate here thorugh discontinous basement membrane Function - endocytose and transport antigens to immune cells in pocket

Question 35

Stem cells of SI

Answer 35

location base of crypts, replace all epithelial cells

Question 36

Submucosa differences in histology of SI

Answer 36

Duadenum - has additional mucous glands called brunner glands - neutralize acidic chyme Jejunum- no unique Ileum -has large peyers patches nodules from submucosa to lamina propria know these

Question 37

Ileocecal Valve

Answer 37

Thick extension of inner circular layer at junction of ileum and cecum

Question 38

Transition to large intesting histology

Answer 38

abrupt transition from villi to no villi

Question 39

Appendix

Answer 39

extends from cecum, four layers (mucosa submucosa, musclaris externa and serosa) Increase in lymph nodes and no absorbtive function

Question 40

Layers of cecum and colon

Answer 40

mucosa lining epithelium - simple columnar no villi see tubular glands, five cell types lamina propria - abundant immune cells many capillaries, no lymph vessels like SI ***** slow metastisis muscularis muscous - helps mucus submucosa - with blood and lymph vessels lymph tissue extendinf from lamina propria in to tsubmucosa muscularis externa - has inner circular layer and then 3 spaces muscluar bands called teniae coli serosa - covers intraperiotneal portions adventitia - located where intestine is in contact with ab wall

Question 41

lieberkuhn in large intestine

Answer 41

into the lamina propria these are tubes again in the cecum and colon

Question 42

Five cell Types In LI

Answer 42

``` absorbtive goblet enteroendocrine stem cells m cells ```

Question 43

absorbtive cells in LI

Answer 43

in luminal surface, aka colonocytes, short microvilli and absorb water and na

Question 44

goblet cells of LI

Answer 44

luminal surface and glands cyrpts goblet shaped release mucos to lube and protect

Question 45

enteroendocrine of LI

Answer 45

in cyrpts, basal secretion of hormone to bloof

Question 46

Stem cells of LI

Answer 46

replace all cells

Question 47

M Cells of LI

Answer 47

located over the lymph noted have the basal pockets and the microfolds on apical Transport antigents in to nodes

Question 48

teniae coli

Answer 48

3 equally spaces muscluar bands helping movement in the muscularis externa

Question 49

Rectum

Answer 49

dilated distal portion of large intestine deeper crypts with more goblet cells no teniae coli adventitia only

Question 50

Anal Canal

Answer 50

Simple columnar - stratified cuboidal to stratifeid squamus non keratinized - becomes keratinized at anus all adventitia

Question 51

Internal and external anal sphincter

Answer 51

internal - thickening of the inner circular layer | external - skeletal muscle