MORPHOLOGY OF THE GI TRACT

Question 1

what transports food from the pharynx to the stomach?

Answer 1

oesophagus

Question 2

where does the oesophagus originate from?

Answer 2

inferior border of the cricoid cartilage C6

Question 3

where does the oesophagus extend to?

Answer 3

cardiac orifice of the stomach T11

Question 4

where does the oesophagus penetrate the diaphragm?

Answer 4

oesophageal hiatus in the central tendon at T10

Question 5

how many sphincters present in the oesophagus?

Answer 5

two

Question 6

names of sphincters and locations

Answer 6

upper oesophageal sphincter- at the junction between the pharynx and oesophagus

lower oesophageal sphincter- between the oesophagus and the stomach

Question 7

what forms the upper sphincter?

Answer 7

cricopharyngeus muscle

Question 8

where is the lower sphincter located? + spinal level

Answer 8

gastro-oesophageal junction at T11

Question 9

what forms the lower sphincter?

Answer 9

oesophagus entering the stomach at an acute angle

walls of the intra abdominal section of the oesophagus are compressed

folds of mucosa occluding the lumen

right crus of diaphragm forming a pinch-cock effect

Question 10

functions of the sphincters

Answer 10

prevent acid reflux

Question 11

sections of the stomach

Answer 11

cardia- surrounds the superior opening of the stomach at T11

fundus- founded, gas filled portion superior to and to the left of the cardia

body- central large portion

pylorus- connects stomach to the duodenum

Question 12

sections of the pyloris

Answer 12

pyloric antrum, pyloric canal and the pyloric sphincter

Question 13

what does the pyloric sphincter demarcate + where?

Answer 13

transpyloric plane, L1

Question 14

anatomical position of stomach

Answer 14

primarily in the epigastric and umbilical regions

Question 15

anatomical relations

Answer 15

superior- oesophagus and left dome of the diaphragm

anterior- diaphragm, greater omentum, anterior abdominal wall, left lobe of liver, gall bladder

posterior- lesser sac, pancreas, left kidney, left adrenal gland, spleen, splenic artery, transverse mesocolon

Question 16

function of pyloric sphincter

Answer 16

controls the exit of chyme from the stomach

Question 17

how many layers in greater and lesser omenta?

Answer 17

two layers of double layered peritoneum, so 4 membrane layers

Question 18

explain structure of greater omentum

Answer 18

hangs down from greater curvature of the stomach and folds back on itself where it attaches to the transverse colon

Question 19

function of greater omentum

Answer 19

contains lymph nodes

Question 20

lesser omentum structure

Answer 20

peritoneal fold arising from the lesser curvature and ascend to attach to the liver

Question 21

function of lesser omentum

Answer 21

attach stomach and duodenum to the liver

Question 22

what do the greater and lesser omentum divide the abdominal cavity into?

Answer 22

greater and lesser sac which communicate via the epiploic foramen

Question 23

pyloric stenosis explained

Answer 23

narrowing of the opening from the stomach to the first part of the small intestine

occurs in babies

Question 24

gastric ulceration explained

Answer 24

break in the inner lining of the stomach or the small intestine due to nSAIDS or bacteria

Question 25

components of the small intestine

Answer 25

duodenum, ileum and jejunum

Question 26

four parts of the duodenum

Answer 26

superior, descending, inferior and ascending form the C shape

Question 27

spinal level of superior section

Answer 27

L1

Question 28

what is the superior section attached to?

Answer 28

liver via the hepatoduodenal ligament

Question 29

descending structures

Answer 29

curves inferiorly around the head of the pancreas marked by the major duodenal papilla lies posteriorly to the transverse colon and anterior to the right kidney

Question 30

inferior structures

Answer 30

travels laterally to the left crosses over inferior vena cava and aorta located inferiorly to the pancreas posteriorly to the superior mesenteric artery and vein

Question 31

ascencing structures

Answer 31

after the duodenum crosses the aorta it ascends and curves anteriorly to join the jejunum at the duodenojejunal flexure

Question 32

is the duodenum intra or retroperitoneal?

Answer 32

retroperitoneal apart from the superior section

Question 33

are the jejunum retro or intra peritoneal?

Answer 33

intraperitoneal

Question 34

demarcation between the jejunum and ileum

Answer 34

there isn't one

Question 35

where does the ileum end?

Answer 35

ileocaecal junction

Question 36

what does the major papilla demarcate?

Answer 36

change in blood supply from coeliac trunk to superior mesenteric artery (from foregut to midgut)

Question 37

attachments

Answer 37

jejunum and ileum are connected to the posterior abdominal wall by mesentery

Question 38

mesentery definition

Answer 38

double layer of peritoneum

Question 39

four parts of the colon

Answer 39

ascending, transverse, descending and sigmoid

Question 40

what is present before the ascending colon?

Answer 40

cecum

Question 41

location of cecum

Answer 41

lies inferiorly to the ileocecal junction

Question 42

is the cecum retro or intraperitoneal?

Answer 42

intraperitoneal

Question 43

structure found on the cecum

Answer 43

appendix

Question 44

appendix explained

Answer 44

narrow, blind ended tube attached to the cecum highly variable positions

Question 45

appendicitis explained

Answer 45

inflammation of the appendix

Question 46

explain structure of colon

Answer 46

ascending colon- retroperitoneal. Meets right lobe of liver and turns right colic flexure/hepatic flexure transverse colon starts, moves from right to left until left colic/splenic flexure- intraperitoneal descending colon- moves inferiorly to pelvis- retroperitoneal (anterior to left kidney) turns medially to form the sigmoid colon

Question 47

next structure

Answer 47

rectum

Question 48

where does the rectum begin?

Answer 48

S3

Question 49

where does the rectum empty into?

Answer 49

anal canal

Question 50

where is the anal canal located?

Answer 50

within the anal triangle of the perineum, between the right and left ischioanal fossae

Question 51

how many sphincters in anus?

Answer 51

2

Question 52

what sphincters + location? + type of muscle

Answer 52

internal anal sphincter- upper 2/3rds of anal canal- involuntary smooth muscle external anal sphincter- lower 2/3rds- voluntary