Stomach

Question 1

what is the anterior and poterior surface of the stomach smmothly rounded with?

Answer 1

peritoneal covering

Question 2

where is the stomach located

Answer 2

superior aspect of the abdomen. It lies in the epigastric and umbilical regions, mostly protected by the lower portion of the rib cage.

Question 3

what is the stomach mostly protected by

Answer 3

lower portion of the rib cage.

Question 4

what are the 4 regions of th stomach and what do they do

Answer 4

Cardia – surrounds the superior opening of the stomach.
Fundus – the rounded portion superior to and left of the cardia.
Body – the large central portion inferior to the fundus.
Pylorus – connects the stomach to the duodenum.

Question 5

desribe the greater curvature

Answer 5

forms the long, convex, lateral border of the stomach. Arising at the cardiac orifice, it arches backwards and passes inferiorly to the left. It curves to the right as it continues medially to reach the pyloric antrum. The short gastric arteries and the right and left gastro-omental arteries supply branches to the greater curvature.

Question 6

descivbe the lesser curvature

Answer 6

forms the shorter, concave, medial surface of the stomach. The most inferior part of the lesser curvature, the angular notch, indicates the junction of the body and pyloric region. The lesser curvature gives attachment to the hepatogastric ligament and is supplied by the left gastric artery and right gastric branch of the hepatic artery.

Question 7

what is superior and what is inferior to th stomach

Answer 7

Superior
Oesophagus, Diaphragm
Inferior Head and neck of pancreas

Question 8

what is anterior and what is posterior to the stomach

Answer 8

ant,
Greater omentum, abdominal wall, left lobe of liver, gall bladder
Posterior Lesser sac, left kidney, left adrenal gland, splenic artery, common bile duct, gastroduodenal artery

Question 9

descibe the inferior oesophageal sphinter

Answer 9

The inferior oesophageal sphincter is located between the oesophagus and the stomach (in contrast to the superior oesophageal sphincter, located in the pharynx).

It is located to the left of the T11 vertebra. Situated immediately superior is the oesophageal hiatus, an opening in the diaphragm through which the oesophagus travels. Histologically, the sphincter is marked by an abrupt change from stratified squamous epithelium to simple columnar.

The inferior oesophageal sphincter is termed a physiological (or functional) sphincter – it does not have any specific muscle (see the oesophagus for more on this).

Question 10

desrive the pyloric sphincter

Answer 10

The pyloric sphincter lies between the pylorus and the duodenum. It controls of the exit of chyme (food and gastric acid mixture) from the stomach.

In contrast to the inferior oesophageal sphincter, this is an anatomical sphincter. It contains smooth muscle, which constricts to limit the discharge of stomach contents through the orifice.

Emptying of the stomach occurs intermittently when intragastric pressure overcomes the resistance of the pylorus. The pylorus is normally contracted so that the orifice is small and food can stay in the stomach for a suitable period. Gastric peristalsis pushes the chyme through the pyloric canal into the duodenum for further digestion.

Question 11

what are the greater and lesser omnta

Answer 11

two structures that consist of peritoneum folded over itself (two layers of peritoneum – four membrane layers).

Question 12

descbe the greater omentum

Answer 12

hangs down from the greater curvature of the stomach. It drapes over the transverse colon and folds back upon itself before reaching the posterior abdominal wall. It features many lymph nodes, which contain macrophages to help combat infections of the GI tract.

Question 13

descbe the lesser omentum

Answer 13

continuous with peritoneal layers of the stomach and duodenum. These two layers combine at the lesser curvature, and ascend to attach to the liver. The main function of the lesser omentum is to attach the stomach and duodenum to the liver.

Question 14

Together, the greater and lesser omenta divide the abdominal cavity into two; the greater and lesser sac. The stomach lies immediately anterior to the lesser sac.,. how do the two se communicate

Answer 14

via the epiploic foramen, a hole in the lesser omentum.

Question 15

lymphatics of the stomachs

Answer 15

The gastric lymphatic vessels travel with the arteries along the greater and lesser curvatures of the stomach. Lymph fluid drains into the gastric and gastro-omental lymph nodes found at the curvatures.

Efferent lymphatic vessels from these nodes connect to the coeliac lymph nodes, located on the posterior abdominal wall.

Question 16

parasympathetic nerve supply of the PNS

Answer 16

comes from the posterior vagal trunks, derived from the vagus nerve.

Question 17

sympathetic nerve supply of the PNS

Answer 17

supply from the T6-T9 spinal cord segments pass to the coeliac plexus. It also carries some pain transmitting fibres.

Question 18

veinous draingage od the stomach

Answer 18

The veins of the stomach run parallel to the arteries. The right and left gastric veins drain into the hepatic portal vein. The short gastric vein, left and right gastro-omental veins ultimately drain into the superior mesenteric vein.

Question 19

arteiral supply of the atomach

Answer 19

The arterial supply to the stomach comes from the coeliac trunk and its branches. Anastomoses form along the lesser curvature by the right and left gastric arteries and along the greater curvature by the right and left gastro-omental arteries:

Right gastric – branch of the common hepatic artery, which arises from the coeliac trunk.
Left gastric – arises directly from the coeliac trunk.
Right gastro-omental – terminal branch of the gastroduodenal artery, which arises from the common hepatic artery.
Left gastro-omental – branch of the splenic artery, which arises from the coeliac trunk.