Stomach Flashcards Preview

ESA 3 - Gastrointestinal System > Stomach > Flashcards

Flashcards in Stomach Deck (102)
Loading flashcards...
1

What are the functions of the stomach? 

  • Stores food
  • Disinfects food
  • Breaks food down in chyme

2

How does the stomach break food down into chyme? 

  • Chemical disruption
    • Acid
    • Enzymes
  • Physical disruption 
    • Motility

3

Where do stomach secretions come from? 

Gastric pits

4

What are gastric pits? 

Indentations in the stomach mucosa that are openings to gastric glands 

5

What do gastric pits contain? 

Neck cells 

6

What do gastric glands contain? 

Parietal, Chief, and G-cells, along with smooth muscle cells

7

Label this diagram

  • A - Gastric pit (opening to gastric gland)
  • B - Mucous epithelium
  • C - Lymphatic vessel 
  • D - Lamina propria
  • E - Muscularis mucosae
  • F - Submucosa 
  • G - Oblique muscle 
  • H - Circular muscle 
  • I - Longitudinal muscle 
  • J - Serosa
  • K - Artery and vein 
  • L - Myenteric plexus
  • M - Gastric pit 
  • N - Gastric gland 
  • O - Mucous cells 
  • P - Neck 
  • Q - Parietal cells 
  • R - Chief cells 
  • S - Smooth muscle cells
  • T - G cell 

8

What substances are secreted by the stomach? 

  • Hydrochloric acid
  • Proteolytic enzymes 
  • Mucus
  • HCO3-
  • Gastrin

9

What proteolytic enzyme is secreted by the stomach? 

Pepsin

10

What is the cellular origin of hydrochloric acid in the stomach? 

Parietal (oxyntic) cells 

11

What is the purpose of HCl secreted by the stomach? 

Acid keeps luminal pH < 2 

12

What is the cellular origin of proteolytic enzymes in the stomach? 

Chief cells 

13

What is the function of proteolytic enzymes in the stomach? 

Non-specifically breaks down proteins to peptides 

14

What is the cellular origin of mucus in the stomach? 

Neck cells (surface cells) 

15

What are the characteristics of stomach mucus? 

  • Sticky
  • Basic

16

Why is stomach mucus sticky? 

So it is not removed easily from the stomach lining

17

Why is stomach mucus basic? 

Due to amine groups on proteins 

18

What is the cellular origin of HCO3- in the stomach? 

Neck cells (surface cells)

19

What is the purpose of HCO3- in the stomach? 

Provides a buffer for Hions

20

Where is HCO3- secreted by neck cells into? 

The mucus

21

What is the cellular origin of gastrin? 

G-Cells

22

What is the function of gastrin in the stomach? 

Binds to surface receptor on parietal cell, stimulating acid and intrinsic factor 

23

Are body fluids acid or alkaline? 

Most are slightly alkaline 

24

What must be true for a slightly alkaline body fluid to secrete H+ ions? 

It must be created in large quantities 

25

Where does the production of a large amount of body fluid with the intent of secreting H+ occur? 

In the mitochondria of parietal cells 

26

How is H+ produced in parietal cells? 

By splitting water into Hand OHions 

27

What happens to OH- ions produced from the splitting of water in parietal cells? 

They combine with CO2 from metabolsim to from HCO3-, which is exported to the blood

28

How much HCO3- enters the blood for every mole of H+ secreted into the stomach? 

1 mole 

29

What allows parietal cells to produce H+ at a high rate? 

They have lots of mitochondria 

30

Can the ions produced in the mitochondria of parietal cells accumulate in the cell? 

No