Foregut GI Tract Organs

Question 1

Function of Esophagus

Answer 1

Transmits food bolus from pharynx to stomach

Question 2

Where does the Esophagus arise from?

Answer 2

Pharynx (laryngopharynx)

Question 3

The Esophagus enters?

Answer 3

Cardia of Stomach

Question 4

The Esophagus is perfused by?

Answer 4

segmental esophageal arteries off anterior descending aorta

Question 5

The Esophagus is innervated by?

Answer 5

Vagus nerve (parasympathetic);
Thoracic sympathetic trunk T1-T4 (sympathetic-motor),

Sensation pathways: unconscious/reflex (vagus) pain (sympathetic)

Question 6

You feel something sharp as you swallow. What nerves transmit pain sensations from the esophagus?

Answer 6

thoracic sympathetic trunk T1-T4

Question 7

When the vagus nerve is stimulated, what is the motor response in the esophagus?

Answer 7

Parasympathetic - increased peristalsis

Question 8

When the thoracic sympathetic trunk T1-T4 is stimulated, what motor response occurs in the esophagus?

Answer 8

Decreased peristalsis

Question 9

If the vagus nerve is injured, what function would be impaired in the esophagus?

Answer 9

Limitations in peristalsis. Bolus getting stuck or caught in the esophagus.

Question 10

If the thoracic sympathetic trunk T1-T4 nerve is injured, what function would be impaired in the esophagus?

Answer 10

Peristalsis could not be slowed down. Sympathetic activation would be impaired. Sympathetic activation decreases peristalsis.

Question 11

Function of the Stomach

Answer 11

Chemically digest (stomach acid) and mechanically digest (muscular action) food bolus

Question 12

The stomach is perfused by?

Answer 12

Celiac trunk via L/R gastric arteries (lesser curvature of stomach)
L/R gastro-omental arteries (greater curvature of stomach)

Question 13

Stomach is innervated by?

Answer 13

Vagus nerve (parasympathetic);
Thoracic sympathetic trunk T5-T9 (sympathetic),
Sensation pathways: unconscious/reflex (vagus)
Pain (sympathetic)

Question 14

When the vagus nerve is stimulated, what occurs in the stomach?

Answer 14

Parasympathetic: increased motility and secretions

Question 15

When the thoracic sympathetic trunk T5-T9 is stimulated, what is the response in the stomach?

Answer 15

Sympathetic.
Contraction of Pylori Sphincter
Inhibit Peristalsis
Decreased Absorption
Decreased Secretions

Question 16

What nerves transmit pain sensations from the stomach?

Answer 16

thoracic sympathetic trunk T5-T9

Question 17

What are the three GI structures of the “foregut”

Answer 17

Stomach, Pyloric Sphincter, First half of duodenum

Question 18

What are the three accessory GI organs? What section of the gut do they belong to, and why?

Answer 18

Liver, Gall Bladder, Pancreas. All belong to the Foregut because branches off the celiac trunk perfuse them.

Question 19

Function of the Liver

Answer 19

Produces bile to digest fats, filters blood from portal circulation

Question 20

Blood supply to the liver is from?

Answer 20

Celiac trunk via proper hepatic artery

Question 21

The liver is innervated by?

Answer 21

vagus nerve (parasympathetic);
thoracic sympathetic trunk T5-T9 (sympathetic),
sensation pathways: unconcious/reflex (vagus) pain (sympathetic)

Question 22

What occurs in the liver when the vagus nerve is stimulated?

Answer 22

Parasympathetic Activation.
Decrease in glucose production/release.
But an Increase in glycogenesis - formation of glycogen to store glucose.

Question 23

What occurs in the liver when the thoracic sympathetic chain T5-T9 nerves are stimulated?

Answer 23

Sympathetic Activation.
Stimulates glucose release. Need glucose to run in fight or flight.
Decrease in glycogenesis.

Question 24

Function of the Gall Bladder

Answer 24

Stores bile, contracts to release stored bile

Question 25

Blood supply of the Gall Bladder

Answer 25

Celiac trunk via cystic artery off proper hepatic

Question 26

Innervation of the Gall Bladder

Answer 26

vagus nerve (parasympathetic); thoracic sympathetic trunk T5-T9 (sympathetic), sensation pathways: unconcious/reflex (vagus) pain (sympathetic)

Question 27

When the vagus nerve is stimulated, what occurs in the gall bladder?

Answer 27

Parasympathetic Activation. Gall Bladder contraction to empty and release bile into the duodenum.

Question 28

When the thoracic sympathetic chain T5-T9 nerves are stimulated, what occurs in the gall bladder?

Answer 28

Sympathetic Activation. Reduction in bile flow out of gall bladder.

Question 29

Your patient is experiencing pain from Gall Stones. What sensory nerves relay this pain information?

Answer 29

pain (sympathetic) thoracic sympathetic trunk T5-T9

Question 30

Function of the Pancreas

Answer 30

Produces digestive enzymes to break down food, bicarbonate to neutralize stomach acid, hormones to regulate sugar metabolism

Question 31

Blood supply to pancreas

Answer 31

Celiac trunk via splenic artery, some supply from gastroduodenal and superior mesenteric arteries (pancreaticoduodenal arteries)

Question 32

Innervation of the pancreas

Answer 32

vagus nerve (parasympathetic); thoracic sympathetic trunk T5-T9 (sympathetic), sensation pathways: unconcious/reflex (vagus) pain (sympathetic)

Question 33

When the vagus nerve is stimulated, what occurs in the pancreas?

Answer 33

Parasympathetic Activation. Relaxation of Hepatopancreatic Sphincter Increase in Insulin Release

Question 34

What occurs in the pancreas when the thoracic sympathetic T5-T9 nerves are stimulated?

Answer 34

Sympathetic Activation Decrease Insulin Production Increase Glucagon Production - raises blood sugar. You need sugar to RUN.

Question 35

Function of the Pyloric Sphincter

Answer 35

Regulate passage of food from the stomach to duodenum

Question 36

Perfusion of Pyloric Sphincter

Answer 36

Celiac trunk via L/R gastric arteries, L/R gastro-omental arteries

Question 37

Innervation of Pyloric Sphincter

Answer 37

Vagus nerve (parasympathetic); Thoracic sympathetic trunk T5-T9 (sympathetic), Sensation pathways: unconscious/reflex (vagus) Pain (sympathetic)

Question 38

What nerves transmit pain sensations from the pyloric sphincter?

Answer 38

thoracic sympathetic trunk T5-T9

Question 39

What is the response of the pyloric sphincter when the vagus nerve is stimulated?

Answer 39

Parasympathetic. Relaxation of sphincter.

Question 40

What is the response of the pyloric sphincter when the thoracic sympathetic trunk T5-T9 is stimulated?

Answer 40

Sympathetic. Contraction of sphincter.

Question 41

The pyloric sphincter demarcates?

Answer 41

muscular sphincter demarcating the border between the stomach and duodenum

Question 42

The Duodenum arises from?

Answer 42

The pylorus

Question 43

The Duodenum enters into?

Answer 43

the Jejunum

Question 44

Function of the duodenum?

Answer 44

Site of additional digestion from products of liver/pancreas, initiate nutrient absorption

Question 45

What perfuses the first half or proximal half of duodenum?

Answer 45

Celiac trunk via gastroduodenal artery,

Question 46

What perfuses the second half or distal half of duodenum?

Answer 46

additional supply from superior mesenteric artery via the pancreaticoduodenal artery

Question 47

What innervates the duodenum?

Answer 47

vagus nerve (parasympathetic); thoracic sympathetic trunk T5-T9 (sympathetic), sensation pathways: unconcious/reflex (vagus) pain (sympathetic)

Question 48

What occurs at the duodenum when the vagus nerve is stimulated?

Answer 48

Parasympathetic. Increased peristalsis, absorption, and secretions in the small intestine.

Question 49

What occurs at the duodenum when the thoracic sympathetic trunk T5-T9 is stimulated?

Answer 49

Sympathetic. Decreased peristalsis, absorption, and secretions.

Question 50

What nerves transmit pain sensations from the duodenum?

Answer 50

thoracic sympathetic trunk T5-T9

Question 51

What organ is not a GI structure but perfused by the celiac trunk via the splenic artery?

Answer 51

Spleen

Question 52

What is the function of the spleen?

Answer 52

Blood reservoir in adult

Question 53

What innervates the spleen?

Answer 53

vagus nerve (parasympathetic); thoracic sympathetic trunk T5-T9 (sympathetic), sensation pathways: unconcious/reflex (vagus) pain (sympathetic)

Question 54

What occurs in the spleen when the thoracic sympathetic trunk T5-T9 is stimulated?

Answer 54

Sympathetic Activation. Splenic contraction. A physiological process that occurs when the spleen releases stored red blood cells (RBCs) into circulation