Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GASTRO > 4: Stomach > Flashcards

4: Stomach Flashcards

(75 cards)

Start Studying
1
Q

What are the functions of the stomach? (3 things)

A
  1. Stores food
  2. Disinfects food
  3. Breaks food → chyme
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does the stomach break food down into chyme? (2 things)

A
  1. Chemical disruption: acid + enzymes
  2. Physical disruption: motility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the indents in the Stomach mucosa called?

A

Gastric pits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do gastric pits open into?

A

Gastric glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the cells of the Gastric Pits?

A

Neck cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the cells of the Gastric Glands? (4 things)

A
  1. Parietal cells
  2. Chief cells
  3. Endocrine cells (G cells)
  4. SMC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do Neck cells secrete? (2 things)

(Gastric Pit Cell)

A
  1. Mucus
    * Sticky so stays on stomach lining
  2. HCO3-
    * Secreted into mucus, provides buffer for H+ ions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do Parietal cells secrete?

(Gastric Gland Cell)

A

HCl

  • Keeps stomach pH below 2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do Chief cells secrete?

(Gastric Gland Cell)

A

Proteolytic enzymes (Pepsin)

  • Breaks down proteins →peptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do Endocrine cells secrete?

(Gastric Gland Cell)

A

Gastrin

Bind to receptor on Parietal cell → stimulates HCl secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the mechanism of HCl secretion? (4 steps)

A
  1. H2O in Parietal cell → H+ + OH-
  2. H+ pumped into Stomach through Canaliculi (invaginations in wall)
    * Canaliculi has proton pump: H+ pumped agains concentration gradient using ATP
  3. OH- combines with CO2 → HCO3-
  4. HCO3- secreted into blood / ECF

H+ and HCO3- secreted at 1:1 ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why are the Canaliculi of the stomachs Parietal cells clinically important?

A

They can be inhibited by Proton Pump Inhibitor Drugs to reduce stomach acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are Parietal cells stimulated by? (3 things)

A
  1. Ach
  2. Gastrin
  3. Histamine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does Ach stimulate Parietal cells? (3 steps)

A
  1. Food arrives → Gastric distension (stretching)
  2. Stretching causes Post-ganglionic PS neurones to release Ach
  3. Ach acts on Muscarinic (M3) receptors on Parietal cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does Gastrin stimulate Parietal cells? (2 steps)

A
  1. Presence of Ach stimulates → Endocrine Cells (G Cells) to secrete Gastrin
  2. Gastrin binds to surface receptors on Parietal cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Gastrin inhibited by?

A

Low stomach pH (feedback control)

Because Gastrin makes Parietal cells make HCl so if pH already low then you don’t neeeeeeed it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does Histamine stimulate Parietal cells? (3 steps)

A
  1. Gastrin + Ach stimulate Mast Cells → release Histamine
  2. Histamine binds to H2 receptors on Parietal cells
  3. Stimulates acid secretion via cAMP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 3 phases of Gastric secretion?

A
  1. Cephalic Phase (High)
  2. Gastric Phase (High)
  3. Intestinal Phase (Low)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How is Gastric secretion stimulated in the Cephalic phase? (High acid) (3 steps)

A
  1. Sight, smell, swallowing → activates PNS
  2. PNS stimulates Ach release
  3. Ach stimulates Parietal cells
  • Directly
  • via Histamine

Called cephalic phase because sight smell and swallowing happens in the head innit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is Gastric secretion stimulated in the Gastric phase? (High acid) (5 steps)

A
  1. When food reaches stomach → Gastric distensions (stretching)
  2. Stretching stimulates Ach release (via Post-ganglionic PS neurones)
  3. Food also buffers acid, increasing the pH, this disinhibits Gastrin → Gastrin secreted
  4. Acid + enzymes breakdown proteins → peptides
  5. Peptides stimulate Gastrin

Called gastric phase because everything happens in stomach innit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How is Gastric secretion inhibited in the Intestinal phase? (Low acid)

A
  1. When chyme leaves stomach → stimulates 2 hormones:
  2. Cholecystokinin (CCK)
  3. Gastric Inhibitory Polypeptide
  4. CCK & GIP antagonise Gastrin → Low acid secretion
  5. No food to buffer acid so pH decreases → low pH inhibits Gastrin → Low acid secretion

Called intestinal phase because food has gone to intestines now innit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What drugs can be used to reduce Gastric acid secretion? (2 things)

A
  1. Anti-histamine
  2. Proton Pump Inhibitor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How does Anti-histamine reduce gastric acid secretion? (2 steps)

A
  1. Inhibits histamine @ H2 receptors (on Parietal cells)
  2. Removes Gastrin / Ach signal amplification
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do Proton Pump Inhibitors reduce gastric acid secretion?

A

Prevent H+ from being pumped through Parietal cell Canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are the properties of stomach mucus? (2 things)
1. Sticky: stays on stomach lining 2. Basic: buffers H+
26
What layer does mucus form in the stomach?
An "unstirred layer" Where ions can't move easily in
27
How does the "unstirred" layer of the stomach buffer H+? (3 steps)
1. H+ ions diffuse into layer from stomach lumen 2. HCO3- secreted into layer from Neck Cells (Gastric Pit Cells) 3. Because layer is unstirred (ion can't move easily in): HCO3- stays close to surface cells → surface pH stays above 6
28
What are HCO3- and Mucus secretions stimulated by?
Prostaglandins * (Which are promoted by most factors that stimulate acid secretion)
29
What things can breach the stomachs defences? (3 things)
1. Alcohol 2. Helicobacter Pylori 3. NSAIDs
30
How does alcohol breach the stomachs defences?
Dissolves mucus → acid attacks stomach
31
How does Helicobacter Pylori breach the stomachs defences?
Infects surface cells → No mucus / HCO3- produced
32
How do NSAIDS breach the stomachs defences?
Inhibit prostaglandins → no HCO3- / mucus produced
33
What can form if the stomach defences are breached?
Peptic ulcers
34
What is the treatment for breached stomach defences / peptic ulcers? (2 things)
1. Reduce acid secretion (anti-histamine / proton pump inhibitors) 2. Abx to eliminate Helicobacter Pylori (if needed)
35
What reflex allows us to eat larger meals?
Receptive Relaxation
36
What is Receptive Relaxation?
Stomach reflex: Gastric fundus dilates when food passes down pharynx + oesophagus
37
How does Receptive Relaxation occur? (3 steps)
1. Food goes down pharynx + oesophagus 2. Neural reflex from Vagus nerve triggers stomach wall relaxtion → stomach pressure doesn't increase 3. Pressure not increasing limits reflux + allows us to eat larger meals
38
What happens if the Vagus nerve is damaged? (Receptive relaxation)
Stomach pressure increase NOT inhibited by Receptive Relaxation → Reflux + Can't eat large meals
39
What are the rhythmic contractions of the stomach? (2 steps)
1. Pacemaker in Cardiac region of Stomach → drives Longitudinal + Circular muscles contrctions 2. Regular _accelerating_ peristaltic contractions from Cardia → Pylorus
40
How is the stomach emptied?
1. Chyme reaches Pyloric region 2. Small squirt ejected into intestine before peristaltic wave comes and shuts it * 3 persistaltic waves / min → 3 squirts / min
41
What are the squirts of gastric emptying affected by? (3 things)
1. Rate of peristaltic wave acceleration 2. Intestinal hormones 3. Fat + low pH slows down emptying
42
What are some Gastric disordes? (4 things)
1. Gastro-oesophageal Reflux Disease (GORD) 2. Peptic Ulcer Disease (PUD) 3. Helicobacter Pylori 4. Gastrits
43
What are the clinical features of Gastro-oesophogeal Reflux Disease (GORD)?
Dyspepsia (heart burn) * Worse @ lying down / bending / hot drinks
44
How is Gastro-oesophogeal Reflux Disease (GORD) diagnosed and investigated? (2 things)
1. Clinical diagnosis done on symptoms alone 2. If Hiatus Hernia suspected: investigate by Endoscopy
45
How is Gastro-oesophogeal Reflux Disease (GORD) managed? (6 things)
1. Lifestyle * Lose weight * Reduce smoking / alcohol * Reduce chocolate + fatty foods 2. Medication * Antacids * Proton Pump Inhibitor → reduces acid secretion from Parietal cells * Anti-histamines (H2 antagonists) → reduces acid secretion from Parietal cells
46
What happens to the stomach cells in Peptic Ulcer Disease (PUD)?
Break in superficial epithelial cells → Penetrates down to Muscularis Mucosa
47
What causes Peptic Ulcer Disease (PUD)?
NSAIDS * Inhibit prostaglandin production → reduces mucus production
48
What are the clinical features of Peptic Ulcer Disease (PUD)? (2 things)
1. Burning epigastric pain * Persistant + severe pain: suggests ulcer penetration into other organs * Back pain: suggests posterior penetration of ulcer 2. Weight loss / anorexia
49
How is Peptic Ulcer Disease (PUD) investigated? (2 things)
1. Investigate H. Pylori infections 2. Endoscopy for older patients → rule out cancer
50
How is Peptic Ulcer Disease (PUD) managed? (2 things)
1. If due to H. Pylori: **Triple Therapy:** * Proton Pump Inhibitors * Abx * Anti-histamine (H2 antagonists) 2. If taking NSAIDs: Stop + review
51
What are the complications of Peptic Ulcer Disease (PUD)? (2 things)
1. Perforations of ulcer → into Peritoneal cavity 2. Gastric outlet obstruction
52
What is Chronic Gastritis caused by?
Helicobacter Pylori
53
What are the features of Helicobacter Pylori? (3 things)
1. Aerobic 2. Produces urease enzyme 3. Resides in stomach of infected person
54
How does Helicobacter Pylori survive in the stomach?
1. Produces urease enzyme → produces ammonia 2. Ammonia neutralised acid → allows H. Pylori to survive
55
How does Helicobacter Pylori damage the stomach? (2 things)
Damages epithelium by: 1. Releasing enzymes 2. Inducing apoptosis
56
How is Helicobacter Pylori diagnosed? (3 things)
1. igG in serum 2. Urea breath test 3. Culture gastric sample (taken by endoscopy)
57
What is the treatment for Helicobacter Pylori?
**Triple Therapy:** * Proton Pump Inhibitors * Abx * Anti-histamine (H2 antagonists)
58
What can chronic gastritis cause?
Ulceration Endocrine cells (G cells) release gastrin (**Hypergastrinaemia**) → increases acid production → ulceration
59
What are the 5 parts of the stomach?
1. Cardia 2. Fundus 3. Body 4. Antrum 5. Pylorus
60
What are the 2 stomach sphincters?
1. Inferior Oesophageal Sphincter 2. Pyloric Sphincter
61
What is the Z line of the GI system?
Where **Squamous** mucosa of _oesophagus_ meets **Columnar** mucosa of _stomach_
62
What is superior to the Z line of the GI system?
Diaphragmatic musculature: forms **LOWER OESOPHAGEAL SPHINCTER**
63
What is the Lower Oesophageal sphincter coupled with to prevent stomach reflex?
Cardiac notch of stomach
64
What is the Pyloric sphincter made out of?
Thickened circular muscle coat
65
What does the Pyloric sphincter of the muscle control?
The squirts of the stomach into the duodenum
66
What is the gastric mucosa like when empty?
1. Longitudinal folds (rugae) 2. Gastric canal forms between folds along Lesser Curvature of stomah → allows saliva & small parts of food → Pylorus
67
How are the different parts of the stomach histologically different?
1. Cardia: * Neck cells → mucus 2. Fundus & Body * Neck cells → mucus * Parietal cells → acid * Chief cells → pepsinogen 3. Pylorus * Neck cells → mucus * Endocrine Cells (G cells) → Gastrin
68
What are the peritoneal folds around the stomach? (2 things)
1. Greater Omentum 2. Lesser Omentum
69
What is the Greater Omentum? (3 points)
1. 4 layered peritoneal fold 2. Hangs down from GREATER curvature of stomach 3. Folds back up → attaches to anterior surface of transverse colon + its mesentry
70
What is the Lesser Omentum? (3 points)
1. 2 layered peritoneal fold 2. Connects LESSER curvature of _stomach_ + proximal part of _duodenum_ → _liver_ 3. Connects stomach to portal triad
71
What is the blood supply tree to the stomach?
72
What is the blood supply to the Lesser Curvature of the stomach?
L & R Gastric Arteries L esse R
73
What is the blood supply to the Greater Curvature of the stomach?
L & R Gastro-omental Arteries
74
What is the blood supply to the Fundus & Body of the stomach?
Posterior Gastric arteries
75
What is the venous drainage of the stomach? (4 things)
1. L & R Gastric → Hepatic portal vein (HPV) 2. Short Gastric → Splenic vein → joins Superior Mesenteric Vein (SMV) → HPV 3. L Gastro-omental → splenic vein → joins SMV → HPV 4. R Gastro-omental → SMV → joins splenic vein → HPV

GASTRO (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions