Embryology of the GI Tract/Stomach

Question 1

What are the three independent parts of the alimentary tract in early embryological development?

Answer 1

Foregut, midgut, hindgut

Question 2

The foregut forms what structures?

Answer 2

Distal esophagus, stomach, and part of the duodenum

Question 3

Where does the foregut end?

Answer 3

Second part of the duodenum at the entrance of the bile duct

Question 4

Where does the midgut begin and end?

Answer 4

Begins are the entrance of the bile duct into the second part of the duodenum and ends with the right 2/3 of the transverse colon

Question 5

Where does the hindgut begin and end?

Answer 5

Begins with the left 1/3 of the transverse colon and ends in the upper part of the anal canal

Question 6

Why are the three embryological divisions of the GI tract important?

Answer 6

The adult derivatives of each have a unified blood supply and autonomic nerve supply

Question 7

All of the blood supply to the foregut, midgut, and hindgut come from what place?

Answer 7

Abdominal aorta

Question 8

What is the blood supply to the foregut?

Answer 8

Branches of the celiac trunk

Question 9

What is the blood supply to the midgut?

Answer 9

Branches of the superior mesenteric artery

Question 10

What is the blood supply to the hindgut?

Answer 10

Branches of the inferior mesenteric artery

Question 11

What is the sympathetic innervation of both the foregut and midgut?

Answer 11

Greater splanchnic nerves (T5-T9) and lesser splanchnic nerves (T10-T11)

Question 12

What is the sympathetic innervation of the hindgut?

Answer 12

Lumbar splanchnic nerves (L1-L2)

Question 13

What is the parasympathetic innervation of both the foregut and midgut?

Answer 13

Vagus nerve

Question 14

What is the parasympathetic innervation of the hindgut?

Answer 14

Pelvic splanchnic nerves (S2-S4)

Question 15

What is the sympathetic effect on the GI tract?

Answer 15

Decreased motility and tone and contraction of sphincters

Question 16

What is the parasympathetic effect on the GI tract?

Answer 16

Increased motility and tone and relaxation of sphincters

Question 17

What are the four major layers of the gut wall?

Answer 17

Mucosa, submucosa, muscularis externa, serosa/adventitia

Question 18

What layer of the gut wall is a mucous membrane (important for absorption) that contains the muscular mucosae with is a thin layer of smooth muscle?

Answer 18

Mucosa

Question 19

Which layer of the gut wall is very vascular?

Answer 19

Submucosa

Question 20

Which layer of the gut wall is a loose connective tissue layer containing blood vessels and lymphatics?

Answer 20

Submucosa

Question 21

What layer of the gut wall is a thick layer of smooth muscle responsible for peristalsis?

Answer 21

Muscularis externa

Question 22

Peristalsis moves in which direction?

Answer 22

Distally

Question 23

The muscularis external consists of what two layers?

Answer 23

Inner circular layer and outer longitudinal layer

Question 24

What is another name for visceral peritoneum of the gut wall?

Answer 24

Serosa

Question 25

What is the name for the connective tissue coat covering retroperitoneal organs?

Answer 25

Adventitia

Question 26

What is the name of the semi-independent regional system of nerves responsible for the gut?

Answer 26

Enteric nervous system

Question 27

Where is the submucosal plexus located?

Answer 27

Within the submucosa near its border with the muscularis externa

Question 28

What do the postganglionic fibers of the submucosal plexus supply?

Answer 28

Muscularis mucosae and mucus secreting glands

Question 29

Where is the myenteric plexus located?

Answer 29

Between the circular and longitudinal layers of muscularis externa

Question 30

What do the postganglionic fibers of the myenteric plexus supply?

Answer 30

Both layers of the muscularis externa

Question 31

What action is the myenteric plexus responsible for?

Answer 31

Stimulation of peristalsis

Question 32

What is the shape of the stomach when empty?

Answer 32

J-shaped

Question 33

What is the capacity of the stomach?

Answer 33

2-3 liters

Question 34

What are examples of foreign things the stomach can absorb?

Answer 34

Some drugs and alcohol

Question 35

The stomach lies in what regions of the abdomen?

Answer 35

Left hypochondriac, epigastric, and umbilical regions

Question 36

What is the function of the stomach?

Answer 36

Storing and mixing food with gastric secretions, therefore converting it into chyme

Question 37

What part of the stomach is where the esophagus joins the stomach (surrounds the cardial orifice)?

Answer 37

Cardia

Question 38

What part of the stomach is above the cardia?

Answer 38

Fundus

Question 39

What part of the stomach is between the fundus and pyloric part?

Answer 39

Body

Question 40

What part of the stomach is the most distal portion and is adjacent to the duodenum?

Answer 40

Pyloric part

Question 41

What is the narrow distal part of the pyloric part of the stomach?

Answer 41

Pyloric canal

Question 42

What is the notch of the stomach called that is between the esophagus and fundus?

Answer 42

Cardial notch

Question 43

What is the notch of the stomach called that is between the body and pyloric part?

Answer 43

Angular incisure

Question 44

Where is the cardial orifice located?

Answer 44

Between the esophagus and fundus

Question 45

Where is the pyloric orifice located?

Answer 45

Between the stomach and duodenum

Question 46

What is the wide proximal part of the pyloric part of the stomach called?

Answer 46

Pyloric antrum

Question 47

What is the distal termination of the pyloric part of the stomach?

Answer 47

Pylorus

Question 48

What two things does the pylorus contain?

Answer 48

Pyloric orifice and pyloric sphincter

Question 49

What is the pyloric muscle?

Answer 49

Circular muscle layer which surrounds the pyloric orifice

Question 50

What does "pylorus" mean?

Answer 50

Gatekeeper

Question 51

Why does the mucous membrane of the stomach have gastric folds (rugae)?

Answer 51

Increased surface area and allows for stomach expansion

Question 52

What is congenital hypertrophic pyloric stenosis?

Answer 52

A tumor-like increase in the size of the pyloric sphincter which reduces the size of the pyloric canal

Question 53

Congenital hypertrophic pyloric stenosis is more common among what gender?

Answer 53

Males

Question 54

What does congenital hypertrophic pyloric stenosis result in?

Answer 54

Projectile vomiting

Question 55

What is the treatment for congenital hypertrophic pyloric stenosis?

Answer 55

Surgical intervention early in infancy

Question 56

What is pylorospasm?

Answer 56

Spasmodic contraction of pyloric sphincter

Question 57

What is the effect of pylorospasm?

Answer 57

Food does not pass easily from the stomach to the duodenum & the stomach becomes overly full leading to vomiting (possibly projectile)

Question 58

Pylorospasm can sometimes be present in what population?

Answer 58

Infants

Question 59

Subluxations of what area could play a role in pylorospasm?

Answer 59

T5-T9

Question 60

What is a gastric ulcer?

Answer 60

A crater-like depression in the mucosa of the stomach

Question 61

What are the causes of a gastric ulcer?

Answer 61

Excess acid secretion (often related to stress) or inadequate mucus barrier (usually related to erosion due to the presence of bacteria)

Question 62

What is the mucous secreted by the stomach like?

Answer 62

Sticky, viscous, and alkaline

Question 63

Subluxation of what sympathetic area could play a role in gastric ulcers?

Answer 63

T5-T9 (affecting the secretion of gastric acid from parietal cells)

Question 64

Where does the stomach lie in reference to the pancreas?

Answer 64

Anterior

Question 65

Where does the stomach lie in reference to the lesser sac?

Answer 65

Anterior

Question 66

Where does the stomach lie in reference to the diaphragm?

Answer 66

Posterior

Question 67

Where does the stomach lie in reference to the left lobe of the liver?

Answer 67

Posterior

Question 68

Where does the stomach lie in reference to the anterior abdominal wall?

Answer 68

Posterior

Question 69

What is the blood supply to the stomach?

Answer 69

Branches of the celiac trunk

Question 70

What is the sympathetic innervation of the celiac plexus to the stomach?

Answer 70

Greater splanchnic nerves (T5-T9)

Question 71

What is the parasympathetic innervation of the celiac plexus to the stomach?

Answer 71

Vagus nerve

Question 72

Where does the celiac trunk lie?

Answer 72

Immediately below the aortic hiatus of the diaphragm as the first unpaired branch from the abdominal aorta

Question 73

What is the smallest branch of the celiac trunk that runs along the lesser curvature within the lesser omentum to anastomose with its right branch??

Answer 73

Left gastric artery

Question 74

What are the two types of branches of the left gastric artery?

Answer 74

Esophageal and gastric branches

Question 75

What is the largest branch of the celiac trunk that runs posterior to the stomach along the superior border of the pancreas to terminate in the spleen?

Answer 75

Splenic artery

Question 76

What are the branches of the splenic artery?

Answer 76

Pancreatic branches, short gastric arteries, left gastro-omental artery, common hepatic artery

Question 77

What branch of the splenic artery goes to the fundus of the stomach?

Answer 77

Short gastric arteries

Question 78

What branch of the splenic artery runs to the right along the greater curvature of the stomach within the greater omentum?

Answer 78

Left gastro-omental artery

Question 79

What branch of the splenic artery runs to the right along the superior border of the pancreas?

Answer 79

Common hepatic artery

Question 80

When does the common hepatic artery become the hepatic artery proper?

Answer 80

After giving off the gastroduodenal artery

Question 81

What branch of the common hepatic artery descends behind the first part of the duodenum?

Answer 81

Gastroduodenal artery

Question 82

What branch of the gastroduodendal artery goes to the superior aspect of the duodenum?

Answer 82

Supraduodenal artery

Question 83

What branch of the gastroduodendal artery runs to the left along the greater curvature of the stomach along the pyloric part within the greater omentum?

Answer 83

Right gastro-omental artery

Question 84

What branch of the gastroduodenal artery passes between the duodenum and head of the pancreas?

Answer 84

Superior pancreaticoduodenal artery

Question 85

What branch of the hepatic artery proper runs along the lesser curvature of the stomach within the lesser omentum to anastomose with its left?

Answer 85

Right gastric artery

Question 86

Which branch of the hepatic artery proper goes to the left lobe of the liver?

Answer 86

Left hepatic artery

Question 87

What branch of the hepatic artery proper goes to the right lobe of the liver?

Answer 87

Right hepatic artery

Question 88

What does the cystic artery supply?

Answer 88

Gall bladder