Stomach

Question 1

For the greater and lesser curvatures, describe the curvature (convex, concave), direction of curvature and length (in relation to other curvature)

Answer 1

Greater curvature: is convex, curves to the left, is longer than the lesser curvature
Lesser curvature: is concave, curves to the right, shorter than greater curvature

Question 2

Describe the 2 surfaces of the stomach and what they face

Answer 2

Parietal surface: cranial facing, faces liver and diaphragm
Visceral surface: caudal facing, faces abdominal viscera (mainly intestines and spleen)

Question 3

The _______ sphincter is connected to the oesophagus and the _______ sphincter is connected to the duodenum

Answer 3

Cardiac sphincter, pyloric sphincter

Question 4

Name the 3 main connective tissues (peritoneum) from the stomach and what they cover/ connected to

Answer 4

Hepatogastric ligament: connects the liver to stomach
Greater omentum: a loose fold along the greater curvature
Lesser omentum: loose fold along the lesser curvature, which extends to the liver

Question 5

Name the 4 ‘sections’ of the stomach and what theyre connected to, also include which is the largest portion.

Answer 5

Cardiac: where the oesophagus connects to the stomach
Fundus: between the body and cardiac, bulges cranially
Body: major part of the stomach
Pyloric antrum: leads to the exit, into the duodenum

Question 6

Name the 4 layers in a cross section of the digestive tube.

Answer 6

Mucosa, submucosa, muscularis externa (tunica muscularis), serosa

Question 7

What are the 2 types of mucosa, what epithelium covers it and what colour are they?

Answer 7

Non-glandular: stratified squamous epithelium. Whitish-colour
Glandular: simple columnar epithelium (secretory), reddish-yellow colour

Question 8

Describe the glands located in the pyloric region and what they secrete

Answer 8

Short, branching, coiling glands opening into deep gastric pits.
Produce mucus/ gastrin

Question 9

Describe the glands located in the cardiac region and what they secrete

Answer 9

Simple, branched, tubular glands producing mucus

Question 10

Describe the glands located in the function region and what they secrete. What is another name for these glands

Answer 10

‘Proper gastric glands’
Tubular glands producing HCl/ enzymes (secretion specific to the stomach)

Question 11

What type of tissue is commonly found in the cardiac region of the stomach (within the mucosa)

Answer 11

diffuse and nobular lymphoid tissue

Question 12

What is the protective function of mucus in the stomach

Answer 12

Protects the stomach epithelia from being damaged by HCl and pepsin

Question 13

What is the lamina propria

Answer 13

The loose connective tissue between the gastric pits/ gastric glands

Question 14

What cells are located within the lamina propria

Answer 14

Lymphocytes, eosinophils, plasma cells, mast cells

Question 15

What 3 types of glands are located in the gastric pits OF FUNDIC GLANDS? (provide both names if more than one name)

Answer 15

Mucous neck cells, chief cells (peptic cells), parietal cells

Question 16

Describe the mucous neck cell epithelia (including type, nucleus, cytoplasm stain)

Answer 16

Epithelia: cuboidal/ low columnar
Nucleus: flat, basal nucleus
Cytoplasm: slightly basophilic (more basic)
Stain purple with PAS stain due to granules

Question 17

Where are mucous neck, chief and parietal cells found?

Answer 17

Mucous neck: found only in the neck of the gastric pit
Chief: mainly in the lower 1/3 of the base/ fundus gland
Parietal: throughout the fundic glands

Question 18

What do mucous neck cells secrete?

Answer 18

Mucus, for protection

Question 19

What do chief/ peptic cells secrete, and what happens to these secretions

Answer 19

Pepsinogen/ prorenin which are converted into active enzymes in the gastric lumen

Question 20

What do parietal cells secrete?

Answer 20

HCl

Question 21

Describe the parietal cell epithelia (including type, nucleus, cytoplasm stain)

Answer 21

Pyramidal shape with a central nucleus
Strongly eosinophilic (pink stain)

Question 22

Describe the chief cell epithelia (including type, nucleus, cytoplasm stain)

Answer 22

Cuboidal/ pyramidal in shape with a basal nucleus
Basophilic (basic - blue stain)

Question 23

Describe the structure of cardiac glands, what type of secretion they produce.

Answer 23

Simple, branched tubular glands
Mucus secreting cells

Question 24

Describe the depth of the gastric pits/ glands of the pyloric glands in relation to glands in the rest of the stomach.

Answer 24

The gastric pits are deeper in the pyloric gland region than in other areas, but the pyloric glands are relatively short, but highly branched

Question 25

What additional cells are located within the pyloric region and what do they do?

Answer 25

Enteroendocrine cells (G-cells) which secrete hormones (primarily gastrin)

Question 26

Which cells secrete serotonin into the bloodstream, and additional stain silver?

Answer 26

Neuroendocrine cells (argentaffin/ enterochromaffin cells)

Question 27

Describe the direction and location of the longitudinal fibres

Answer 27

2 major longitudinal bands over the greater and lesser curvatures (parietal/ visceral surfaces)

Question 28

Name the 3 muscular fibres located within the stomach.

Answer 28

Longitudinal, circular, internal oblique

Question 29

Describe the direction and location of the circular fibres and what location/s they're thickest.

Answer 29

Present in body/ pyloric region, thickest at pylorus which forms the pyloric sphincter

Question 30

Describe the direction and location of the internal oblique fibres

Answer 30

Present in fundus/ cardia, closely packed in the cardiac loop, where they combine with the circular layer to form the cardiac sphincter

Question 31

What centre do the lymphatics drain to from the stomach?

Answer 31

Coeliac lymph centre

Question 32

What 4 nodes are includes in the coeliac lymph centre?

Answer 32

Gastric, coeliac, pancreaticoduodenal, splenic

Question 33

Which plexus's are linked to the enteric nervous system in the gut wall? (provide both names)

Answer 33

Myenteric (auerbach's) and submucosal (Meissner's)

Question 34

What are the 3 main branches of the coeliac artery>

Answer 34

Left gastric, splenic, hepatic

Question 35

What branch of the coeliac artery does the stomach receive the most amount of blood from?

Answer 35

Left gastric a.

Question 36

What organ does the splenic artery supply blood to, and what branch does it give off?

Answer 36

Spleen Left gastroepiploic a.

Question 37

What organ does the hepatic artery supply blood to, and what branch/s does it give off?

Answer 37

Liver Right gastric a., right gastroepiploic a.

Question 38

Which curvature do the left and right gastric arteries run along. Do they anastomose?

Answer 38

Run along the lesser curvature, yes

Question 39

Which curvature do the left and right gastroepiploic arteries run along. Do they anastomose?

Answer 39

Greater curvature, yes

Question 40

Which vein do the venous (de-oxygenated) blood in gastric veins flow through to reach the liver?

Answer 40

Hepatic portal vein

Question 41

Does the sympathetic or parasympathetic innervation influences increase in digestive motility?

Answer 41

Parasympathetic

Question 42

Name the 3 sympathetic ganglia that supply the coeliac a., cranial mesenteric a., and caudal mesenteric a.

Answer 42

Coeliac ganglion, cranial mesenteric ganglion, caudal mesenteric ganglion

Question 43

What is the vagosympathetic trunk?

Answer 43

The combination of sympathetic/ parasympathetic fibres travelling to the head in the thoracic cavity

Question 44

Name the 4 branches the vagus nerve (parasympathetic) divides into, what region of the oseophagus does this occur at?

Answer 44

Left dorsal vagus n., right dorsal vagus n., left ventral vagus n., right ventral vagus n. Occurs near the caudal 1/3 of the oesophagus

Question 45

Name the branches which combine and what they're called (from the vagus n.), and which hiatus the n.s pass through.

Answer 45

Right dorsal vagus n. + left dorsal vagus n. -> dorsal vagus n. Left ventral vagus n. + right ventral vagus n. -> ventral vagus n. Joining occurs post oesophageal hiatus