Overview of GI organs (anatomy)

Question 1

What are the accessory digestive organs?

Answer 1

the salivary glands, liver, gallbladder, and pancreas

Question 2

The Pharynx is a common chamber shared by the digestive and respiratory systems. It is a…………… tube that transports the bolus of food from the oral cavity to the esophagus during swallowing

Answer 2

musculofibrous

Question 3

The digestive system from the distal…………… to the distal sigmoid colon is located within the abdomen.

Answer 3

esophagus

Question 4

The esophagus is a……… tube connecting the pharynx and the stomach. Does it traverse the diaphragm?

Answer 4

muscular

Yes, it traverses the diaphragm to end at the stomach within the abdominal cavity.

Question 5

What is associated with the esophagus as it enters the abdominal cavity?

Answer 5

The anterior & posterior vagal trunks.

Question 6

What does the anterior vagal trunk consist of?

Answer 6

consists of several smaller trunks whose fibers mainly come from the Left vagus nerve

Question 7

What does the posterior vagal trunk consist of?

Answer 7

Consists of a single trunk whose fibers mostly come from the Right vagus nerve.

Question 8

What is the arterial supply of the esophagus?

Answer 8

• Esophageal branches from Left gastric artery (celiac trunk)
• Esophageal branches from the left inferior phrenic artery (abdominal aorta)

Question 9

The esophagus is guarded at both ends by muscular sphincters. What is the role of each?

Answer 9

• Upper esophageal sphincter: helps prevent the entrance of air during respiration and is a secondary line of defense against reflux of gastric contents.
• Lower esophageal sphincter: located at the esophageal hiatus of the diaphragm, and guards against gastro esophageal reflux.

Question 10

Why is prevention of the reflux of gastric contents into the esophagus important?

Answer 10

the esophagus’ epithelium is vulnerable to damage from repeated exposure

Question 11

The stomach is a dilated portion of the digestive tract where food accumulates and undergoes partial enzymatic digestion into semi-liquid chyme. The stomach produces:

Answer 11

Hydrochloric acid and digestive enzymes.

Question 12

What are the 4 parts of the stomach?

Answer 12

• Cardia/cardiac region: at the gastroesophageal junction

−Fundus: the dilated superolateral part

−Body

−Pylorus: Funnel-shaped part which consists of a wide pyloric antrum leading into a narrow pyloric canal

Question 13

The pylorus is marked by a pyloric constriction, and contains the pyloric sphincter. This surrounds the distal opening of the stomach, known as the…………………

Answer 13

pyloric orifice

Question 14

Describe the lesser and greater curvatures of the stomach.

Answer 14

• The lesser curvature faces superiorly and to the right.
• The greater curvature faces inferiorly and to the left.

Question 15

The………….. notch lies in the superior angle created when the esophagus enters the stomach, while the…………….. is a bend on the lesser curvature.

Answer 15

Cardial

Angular incisure

Question 16

What is the primary site for the absorption of nutrients, and the longest part of the GI tract?

Answer 16

The small intestine

Question 17

The small intestine extends from the pylorus to the ileocecal junction. It consists of what?

Answer 17

−Duodenum

−Jejunum

−Ileum

Question 18

What are the surface modifications of the mucosal lining of the small intestines, that increases the surface area for absorption?

Answer 18

− Circular folds (plicae circulares) of mucosa-submucosa

− Villi, which are fingerlike projections of mucosa

− Microvilli, microscopic projections on absorptive cells of the mucosa.

Question 19

Where is the specific location of the duodenum?

Answer 19

It forms a C-shaped loop around the head of the pancreas. It is continuous with the jejunum at the duodenojejunal junction.

Question 20

What are the four parts of the duodenum?

Answer 20

−Superior (first) part

−Descending (second) part

−Inferior/horizontal (third) part

−Ascending (fourth) part

Question 21

What is the duodenal cap, and why is it clinically important?

Answer 21

The first 2 cm of the duodenum is called the duodenal cap, or ampulla, which has a distinct radiographic appearance. It is clinically important because it is the most frequent location of peptic ulcers!

Question 22

The duodenum receives the common bile duct (carrying bile from the liver) and the main pancreatic duct (carrying pancreatic enzymes) in its…………….. part.

The bile duct and main pancreatic duct usually join in a common chamber, called the……………., which drains into the duodenum at the……………………….

Answer 22

descending

hepatopancreatic ampulla

major duodenal papilla

Question 23

The duodenojejunal junction is suspended from the diaphragm by………………….

Answer 23

the suspensory muscle of the duodenum (ligament of Treitz).

Question 24

The duodenojejunal junction is an important clinical landmark. Why?

Answer 24

It is the junction between upper GI bleeding and lower GI bleeding, which have different clinical characteristics.

Question 25

The jejunum and ileum are the more distal parts of the small intestine. The jejunum forms the proximal…….. and is located mainly in the…………. quadrant of the abdomen. The ileum forms the distal………….. and is located mainly in the……………….. quadrant.

Answer 25

2/5

left upper quadrant

3/5

right lower quadrant

Question 26

The ileum may have a remnant of embryonic development, called the…………………, attached to it. This is approximately two feet from the ileocecal junction.

Answer 26

ileal (Meckel’s) diverticulum

Question 27

What is the large intestines known for?

Answer 27

Water absorption

Question 28

What distinguishes the large intestines from the small intestines?

Answer 28

− Omental appendices (appendices epiploicae) (small fatty projections)

− Teniae coli (three bands of longitudinal smooth muscle)

− Haustra

Question 29

What are the portions of the large intestines?

Answer 29

• Cecum and the appendix (which hangs from the cecum below the ileocecal junction)
• Colon (Ascending, Transverse, Descending, Sigmoid)
• Rectum
• Anal canal

Question 30

The ileocecal junction and cecum may be sites of intestinal obstruction. What can happen here?

Answer 30

− Intussusception: the telescoping of a proximal segment of the intestine into a more distal part

−Volvulus: twisting of the intestine on itself

− Gallstone ileus: in which a gallstone blocks the ileocecal junction

Question 31

The appendix (vermiform appendix) is an intestinal diverticulum that contains lymphoid tissue. It has a short mesentery, known as the………………….

Answer 31

mesoappendix

Question 32

The appendix is variable in position, which can complicate the diagnosis of appendicitis. An estimated 20% of cases are misdiagnosed! most commonly, the appendix is……………….. in position.

Answer 32

retrocecal

Question 33

Acute inflammation of the appendix (acute appendicitis) is a SURGICAL emergency. The appendix may become gangrenous or perforate, causing infection of the peritoneal membrane lining of the abdominal cavity. This is known as…………………..

Answer 33

peritonititis

Question 34

4 parts of the colon:

Answer 34

−Ascending colon

−Transverse colon

−Descending colon

−Sigmoid colon

Question 35

The ascending colon meets the transverse colon at the………………… flexure, while the transverse colon meets the descending colon at the………………… flexure.

Answer 35

right colic (hepatic)

left colic (splenic)

Question 36

The sigmoid colon is an S-shaped loop of large intestine. It meets the rectum anterior to vertebra…………. within the pelvic cavity.

Answer 36

S3

Question 37

The rectum and anal canal are the terminal parts of the large intestine. Where is each located?

Answer 37

• Rectum is located in the pelvis
• Anal canal is located in the perineum