Gastric Motility and Pancreatic Function Flashcards Preview

Alimentary System > Gastric Motility and Pancreatic Function > Flashcards

Flashcards in Gastric Motility and Pancreatic Function Deck (18):
1

The enteric nervous system is under control by what systems?

Parasympathetic and sympathetic nervous systems

2

What is the main parasympathetic input to the enteric nervous system?

Vagus nerve

3

What is the main sympathetic input to the enteric nervous system?

Splanchnic nerve

4

What effect does the parasympathetic system have on the GI tract?

Stimulatory - increases secretion and motility

5

What effect does the sympathetic system have on the GI tract?

Inhibitory - except on salivation, decreases secretion and motility

6

Gastric acid in the duodenum is neutralised by _ which is secreted from _

Bicarbonate
Brunner's gland duct cells

7

Bicarbonate combines with gastric acid to produce

Carbonic acid, which then breaks down to produce water and carbon dioxide

8

What three mechanisms control gastric acid secretion and how do they control it?

Neurocrine - vagus/local reflexes
Endocrine - gastrin
Paracrine - histamine

9

What will precursors to eating (sight, smell, taste of food) trigger in the stomach?

Acid production

10

What does stomach acid do to any bacteria ingested?

Instantly sterilises it

11

In what phase is stomach acid produced in response to precursors to eating?

Cephalic phase

12

Precursors to eating stimulate the vagus nerve which increases its stimulation of the stomach to release

ACh which stimulates the parietal cells to produce acid

13

Precursors to eating stimulate the vagus nerve which increases its stimulation of the G cells which produce

gastrin which stimulates parietal cells to produce acid

14

Gastrin in the stomach stimulates the ECL cells which

release histamine which stimulates the parietal cells to produce acid

15

Gastric acid secretion is also stimulated in what phase?

The gastric phase

16

Distension of the stomach in the gastric phase triggers

vagal/enteric reflexes which release ACh, stimulating parietal cells and producing acid

17

Peptides in the lumen stimulate what cells?

G cells

18

What do G cells produce?

Gastrin which stimulates parietal cells and produces acid