Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy 2 > Lect 8 GI tract > Flashcards

Lect 8 GI tract Flashcards

1
Q

Alimentary canal

A

oral cavity ->
pharynx - transport ->
esophagus - transport ->
Stomach - primarily chemical digestion; continued mechanical digestion ->
Small intestine- continued chemical digestion; absorption ->
Large intestine - absorption (h2o + electrolytes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

pharynx

A

provides communication bw nasal + oral cavities and larynx/esophagus
-serves as passage for air and food
-mostly stratified squamous non keratinized epi
-respiratory ares lined with pseduostratified respirator epi
3 regions: naso, oro and laryngopharynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

4 layers of alimentary wall

A

layers modified based on function

mucosa, submucosa, muscularis externa, serosa or adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

mucosa

A

lining epithelium - varies
lamina propria - loose CT
muscularis mucosae - smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Submucosa

A

Dense irregular CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Muscularis externa

A

smooth muscle - inner circular/outer longitudinal- all regions except upper 2/3 of esophagus, which is skeletal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

serosa/adventitia

A

serosa - mesothelium and underlying CT

adventitia - CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

esophagus mucosa

A

lining epithelium: SSNKE
lamina propria - loose CT w. lymphatic nodules and diffues lymphatic tissue (MALT) scattered throughout; esophogeal cardiac glands
muscularis mucosae: smooth muscle, organizes in the esophagus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

esophogeal cardiac glands

A

location: lamina propria of distal esophagus only
function: secrete mucus and protects esophagus from acidic gastric fluids that reflux into esophagus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

esophagus submucosa

A

Dense irregular CT, w/ elastic fibers that allows for expansion for food bolus; esophageal glands proper, location of Meissner’s plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Esophageal glands proper

A

location: throughout length of the esophageal mucosa
function: mucus product lubricates the wall, offers protection and facilitates transport of food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Esophagus muscalaris externa

A

inner circular/outer longitudinal
skeletal muscle replaced such that swalling begins as controlled voluntary movement but ends in involuntary peristalis
Upper 1/3: skeletal
middle 1/3: mixed
Lower 1/3: smooth
Auerbachs plexus: between inner circular/ outer longitudinal layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Esophagus adventitia/serosa

A

thoracic cavity: an adventitia binds esophagus to other structure within the thoracic cavity (trachea, aorta)
abdominal cavity: serosa covers the intra-abdominal portion of the esophagus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Gastroesophageal junction

A 
Features: 
abrupt change in the epithelium from Strat Squamous NKE to simple columnar epithelium
Gastroesophageal sphincter (physiologic sphincter) increased tone in the inner circular layer of the muscularis externa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Stomach regions

A

cardia, fundus, body, pylorus
(fundus & body are same histologically)
4 layers of wall
major function: physical and chemical digestion -> process food into chyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

stomach mucosa

A

Lining epithelium - simple columnar

covers the luminal surface, gastric pits, glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Lining epithelium of stomach mucosa

A

Six cell types. 1. surface mucous cells 2. mucous neck cells 3. stem cells 4. enteroendocrine cells 5. Parietal cells 6. chief cells
(glands are lined by 3-5 cell types)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

surface mucous cells

A

Location: luminal surface of stomach and gastric pits

structure: simple columnar cells; apical mucigen granules; basal nucleus
function: release mucin, which w/ water, forms a viscous alkaline mucus high in bicarbonate ion concentraion; buffers and coats the luminal surface and protects the epithelium from the acidic luminal contents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

glands of the stomach mucosa

A

Gastric (fundic) - in body and fundus
contains mucous neck, stem, enteroendocrine, parietal and chief cells

Cardiac glands- in cardia
contains mucous neck, stem, enteroendocrine, may have some parietal cells

pyloric glands: in pylorus
contain mucous neck cells, stem cells, enteroendocrine cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

mucous neck cells

A

location: isthmus and neck of cardiac, pyloric and gastric glands (small clusters or individually)
structure: columnar cell; may appear less regular in shape because of compression by adjacent cell; apical mucigen granules, basal nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Function of mucous neck cells

A

contribute to mucous blanket, produce a less alkaline mucus compared with surface mucous cells (although they look the same as mucous cells, their secretions are much different)
protect parietal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

stem cells of stomach mucosa in glands

A

Location: isthmus and neck of cardiac, pyloric and gastric glands
Structure: columnar cells
Function: stem cell for all epithelial cell types in the stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

enteroendocrine cells

A

location: primarily at base of cardiac pyloric and gastric glands
Structure: basally located secretory granu

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

function of enteroendocrine cells

A

basal secretion of various hormones into lamina propria (blood vessels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Parietal cells of the stomach glands

A

Location: scattered through out gastric glands (few in cardiac)
Structure: large; triangular shape with intracellular canaliculi with microvilli
Cytoplasm is eosinophilic due to abundant mitochondria, which are necessary to fuel ion pumps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

function of parietal cells

A

produce hydrochloric acid

does not secrete HCl in its final form; H+ and Cl- secreted separately -> combine in the lumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Chief cells

A

location: base of gastric glands
structure: apical granules (zymogen granules) contain proenzyme pepsinogen
Basal cytoplasm is basophilic due to presence of rER that synthesize protein for secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

function of chief cells

A

secrete pepsinogen
-once in contact with acidic environment, pepsinogen is converted to pepsin, a digestive enzyme
secrete gastric lipase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Submucosa of the stomach

A

dense irregular CT
contains neurovascular structures, including Meissner’s nerve plexus (supplies local vessels & muscularis mucosae
no glands

30
Q

Muscularis externa of the stomach

A

3 layers: inner oblique, middle circular, outer longitudinal

  • auerbach’s nerve plexus - between muscle layers provides innervation
  • mixes chyme and moves contents toward duodenum
31
Q

serosa

A

covers entire stomach

32
Q

pyloric sphincter

A

location: junction of pyloric stomach and duodenum

formed by a thickening of the middle circular layer of the muscularis externa

33
Q

small intestine

A

3 regions: duodenum, jejunum, ileum

function: complete digestion, absorb nutrients

34
Q

absorptive features of small intestine

A

plicae circulares - series of permanent circular folds; mucosa and submucosa
villi- evaginations of mucosa - lined with simple columnar epi with a core of lamina propria
microvilli - located at the apical aspect of enterocyte/absorptive cells (mucosa)

35
Q

mucosa of the small intestine

A

lining epithelium - simple columnar epi covers villi and intestinal glands/crypts (of Lieberkuhn
six cell types: Enterocytes, goblet cells, enteroendocrine cells, paneth cells, M-cells, stem cells

36
Q

Enterocytes of lining epi of small intestine

A

location - line luminal surface with villi, migrate from crypt: become fully mature cells as they migrate out of the crypt

37
Q

Function of enterocytes of small intestine

A

absorbtive role: specialized for transport of nutrients from lumen to the circulatory system
Secretory role: glycoprotein enzymes in the glycocaylx are secreted by the enterocytes and have a digestive role - secrete water to maintain chyme consistency

38
Q

Goblet cells

A

locations: line the luminal surface of villi and crypts, scattered among the enterocytes, increase in number from duodenum toward distal large intestine
structure: characteristic ‘goblet’ shape with apical accumulation of mucigen granules

39
Q

function of goblet cells

A

mucin is released apically, combines with water to form a mucous product which lubricates and protects the epithelium

40
Q

enteroendocrine cells of the small intestine

A

location: scattered along villi and crypts
structure: basally secretory granules
function: release various hormones

41
Q

paneth cells of the small intestine

A

Location: base of intestinal crypts
Structure: apical eosinophilic granules that contain lysozyme
Function: lysozyme digests the cell wall of certain microorganisms and bacteria

42
Q

M cells of the small intestine

A

location: mainly overlie large lymphatic nodules
structure: Apical- lack microvilli but have apical microfolds
basal: large intracellular pockets; immune cells migrate here through the discontinuous basement membrane

function: endocytose and transport antigens to underlying immune cells

43
Q

stem cells of the small intestine

A

location: base of intestinal crypts
function: replace all lining epithelial cell types

44
Q

lamina propria of small intestine

A

loose CT extends into the core of each intestinal villus and surrounds intestinal crypts/glands
contains fenestrated capillaries, lymphatic vessel (lacteal), smooth muscle fibers, diffues lymphatic tissue (MALT) and lymphatic nodules

45
Q

Muscularis mucosae of small intestine

A

movement of villi

46
Q

submucosa of the small intestine

A

dense irregular connective tissue
includes meissner’s nerve plexus as well as blood and lymph vessels
regional differences exist in duodenum, jejunum and ileum

47
Q

submucosa of the duodenum

A

large mucous glands (brunner glands)
mucus neutralizes acidic chyme entering the duodenum and thereby 1) offers protection to the epithelium and 2) provides optimal pH for pancreatic enzymes

48
Q

submucosa of the jejunum

A

no unique histological features

absence of brunners glands and peyers patches

49
Q

submucosa of the ileum

A

large lymphoid nodules called Peyer patches; these extend into the lamina propria

50
Q

muscularis externa of small intestine

A

inner circular and outer longitudinal layers

bw 2 muscle layers is auerbach’s plexus which is important in peristalsis

51
Q

serosa of small intestine

A

covers majority of small intestine

52
Q

adventitia of small intestine

A

located where the duodenum is in contact with posterior abdominal wall

53
Q

Large intestine structure

A 
Ileocecal valve
appendix
colon (ascending, transverse, descending, sigmoid)
Rectum
anal canal
4 layer wall
54
Q

large intestine function

A

absorption of water and Na+, indigestible material (feces) is formed and propelled by peristalsis through large instestine -> expelled

55
Q

Ileocecal junction

A

ileocecal valve - thickened extension of the inner circular layer of the muscularis externa at the junciton between the ileum and cecum
Transition in the lining epithelium from the small intestinal with villi to the large intestine without villi

56
Q

appendix

A

extends from the cecum
has the typical four layer wall
similar to other regions in large intestine except:
Greater density of lymphatic nodules
the appendix has little or no absorptive function

57
Q

mucosa of the cecum/colon

A

Lining epithelium: simple columnar, no villi but has numerous straight tubular glands/crypts (of Lieberkuhn) that extend into the lamina propria

58
Q

mucosa of the cecum/colon cell types

A 
5
absorptive cells
goblet cells
enteroendocrine cells
stem cells 
m cells
59
Q

absorptive cells of large intestine

A

aka colonocytes/enterocytes
Location: luminal surface and glands/crypts
Structure: columnar, short microvilli
Function: absorb water and Na+

60
Q

Goblet cells of large intestine

A

Location: luminal surface and glands/crypts

Structure/function: goblet shaped; mucus lubricates and protects epithelium

61
Q

Enteroendocrine cells of large intestine

A

Location: crypts/glands (primary base)

Structure/function: basal secretion - hormone

62
Q

stem cells of large intestine

A

Location: crypts/glands

Structure/function: replace epithelial cell types

63
Q

m cells of large intestine

A

location: overlie lymphatic nodules

Structure/function: apical microfolds, basal intracellular pockets; transport antigens to underlying immune cells

64
Q

lamina propria of large intestine

A

loose CT with abundant immune cells (moreso than small intestine) serves to protect body from the vast bacterial population

  • numerous capillaries into which water and sodium are absorbed
  • no lymphatic vessels in LP; organize around muscularis mucosae (which may slow rate of metastasis)
65
Q

Muscularis mucosae of large intestine

A

enhances the expulsion of mucus from glands

66
Q

large intestine submucosa

A

dense irregular CT, meissner’s nerve plexus as well as blood and lymph vessels
lyphoid tissue seen extending from the lamina propria into the submucosa

67
Q

Muscularis externa of large intestine

A

cecum and colon have the typical inner circular layer, but instead of uniform outer longitudinal layers, they have 3 equally spaced muscular bands, the TENAI COLI

between these two muscle layers is Auerbach’s nerve plexus , important for peristalsis

68
Q

serosa of large intestine

A

covers the intraperitoneal portions of the large intestine

69
Q

adventitia of the large intestine

A

located where the large intestine is in contact with the posterior abdominal wall

70
Q

Rectum

A

large intestine
dilated distal portion of the large intestine
similar histology to the colon with variation that include:
Crypts/glands are deeper with more abundant goblet cells
typical inner circular/outer longitudinal layers of muscularis externa (no teniae coli)
adventitia only

71
Q

anal canal

A

upper 1/3: simple columnar epi
middle 1/3: stratified cuboidal epi
lower 1/3: stratified squamous non keratinized epi (transitions to stratified squamous keratinized at anus

internal anal sphincter is formed by a thickening of inner circular layer of the muscularis externa
external anal sphincter is skeletal muscle

Adventitia only

Anatomy 2 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions