GI disease

Question 1

the gastric mucosa is made up of pits and glands that line the stomach, explain what each part includes

Answer 1

PIT:
- mucus/bicarbonate secretion= mucus acts as a protective layer stopping HCI damaging lining and bicarbonate neutralises the acidity of stomach
- neck cells= regenerates gastric mucus cells as those before damaged by HCI

GLAND:
- parietal cells= make HCI and IF
- endocrine cells= release gastrin which regulates HCI secretion
- Enterochromaffin cells= secrete histamine, regulate gastric acid secretion
-chief cells=pepsinogen(protein digestion) turns to pepsin when exposed to acidicity

Question 2

3 protections against stomach acid

Answer 2

1. gastric mucus barrier=layer of mucus in the stomach lining
2. mucus gel barrier= gel over inner surface
3. bicarbonate ions= neutralise acid

Question 3

what is peptic ulcer?

Answer 3

• open sores in lining of stomach/SI

Question 4

what can excess pepsin and HCI lead to?

Answer 4

• peptic ulcer
• break of protective mucus barrier = damage to stomach/lntest lining
• erosion

Question 5

what is HP( Helicobacter pylori)?and what does it convert?

Answer 5

• is the cause of peptic ulcers
• converts urea to ammonia so it can survive

Question 6

what does HP lead to?

Answer 6

inflammation in stomach lining = damage to gastric mucosa

Question 7

what is coeliac disease and what triggers it?

Answer 7

gluten consumption= causes inflammation in small intestine

Question 8

what does inflammation in small intestine lead to?

Answer 8

damage and flattening of villi so hard absorb nutrients ( finger-like hair that surface area increase for absorption)

Question 9

3 key features of coeliac

Answer 9

1. villi loss
2. elongated crypt(pits) under damaged villi to help speed up new formation of cells
3. inflammatory cell infiltrate= increase inflammatory cells in affected area of SI

Question 10

define Crohn disease:

Answer 10

an autoimmune disease where body attacks own healthy tissues in GI tract by mistake
- has skip inflammatory lesions

Question 11

where does the inflammation affect in the Crohn disease?

Answer 11

full thickness of bowel walls

Question 12

what can develop in the affected areas within crohn disease?and what can form?

Answer 12

• fissures can develop in area
• fistulae (abnormal connection between parts in GI tract) can form

Question 13

define Ulcerative colitis

Answer 13

condition that affects colon

Question 14

what can Ulcerative colitis lead to?

Answer 14

• bleeding in colon
• inflammation and lesions are spread in colon
• doesnt have skip lesions (meaning inflammation is continuous along the colon without healthy segments in betwee)

Question 15

in Ulcerative colitis what does the inflammation affect?

Answer 15

• mucosal lning of colon
• long term= cancer
• swollen mucosa
• plasma cells can appear