the digestive system Flashcards

(76 cards)

1
Q

the mouth

A

mobility: mastication of food by teeth and tongue
digestion–> amylase produced by salivary glands breaks down starch
absorption: non
secretion: amylase

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

osephagus

A

mobility- peristalsis
digestion- null
secretion: of mucosa (lube)
absorption: null

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

stomach

A

motility: contraction beings in the funds where s.muscle is stimulated- 3 sub units of the stomach fire APs; either tonic or phasic
absorption- some e.g. water
digestion- pepsin hydrolyses proteins and contraction produces chyme

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

s.intestine

A

motility: peristalsis
secretion: proteases, carbhohdrases and lipase
absorption: sugars, amino acids and fatty acids by villi
digestion- secretion, peristalsis, absorption

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

l.intestine

A

motility: segmentation contractions, antiperistalric and mass movement
secretion: mucosa and bicarbonate
absorption: water
digestion: removes waste product

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

accessory organs

A
liver- bile an blood processor
gall bladder-storage of bile
pancreas- enzymes
appendix stores healthy bacteria
salivary glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

polysaccharides digestion

A

broken down to disaccharides and other smaller sugars e.g. maltose by amylase in the saliva.
-then further broken down by enzymes found on the brush boarder to monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

monosaccharides

A

galactose
glucose
fructose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

fat molecule

A

3 fatty acids 1 glycerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

fat present in s intestine..

A

stimulates the pancreas to release lipase and the gall bladder to release bile

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

pro enzyme of pepsin

A

pepsinogens–> acid content of the stomach activates pepsinogens to pepsins

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

functions of the appendix

A
  • protect good bacteria
    e. g. when an individual has diarrhoea and loses lots of bacteria, the appendix can store good bacteria that can help re-populate the digestive system to keep you healthy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

patients who have had their appendix removed are..

A

4x more likely to have irritation in their l intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

where interstitial cells of canal located

A

fundus (pacemaker cells)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

BER

A

basic electrical rhythm 3 per min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

where are enzymes and acid produced in the stomach

A

cardia

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

what character of the stomach means that its capacity can increase so much

A

the rugae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

where does most mixing and churning occur in the stomach

A

antrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

pyloric antrum

A

nearer body

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

pyloric canal

A

empties into the duodenum

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

mains parts of s.intestine

A

duodenum
jejunum
iieum

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

main parts of large intestine

A

cecum, appendix, ascending transverse and descending colon, sigmoid and anus and rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how can too much fatty foods cause acid reflux

A

not due to an excess of acid but due to a malfunction of the gastrosphogeal sphincter- e.g. if it loses tone it won’t fully close.

fatty foods causes heartburn due to two reasons:

1) lipids cause the LEA to relax, easier for reflux to occur
2) lipids cause pyloric valve to contract tighter, so food is held in the stretch for longer- higher chance of reflux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

coeliac disease

A

an autoimmune disease- immune system mistake gluten for a pathogen and attack it.
This causes villi to be broken down and they lose their important surface area (flattened)

-can cause rapid weight loss due to less nutrient being absorbed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
symptoms of eating too much fatty food
bloating acid reflux and heartburn increased risk of heart disease
26
to alleviate symptoms of coeliac disease
no gluten must be eaten
27
gastric emptying is largely controlled by factors in the...
duodenum
28
factors in the stomach that influence gastric emptying
- amount of chyme being stored - stomach distention - fluidity of the chyme
29
factors in the s.intestine that influence gastric emptying
-if fat, acid, hypertonicity, distention is in the s.intestine then it won't signal to the stomach to empty
30
what causes diarrhoea
when water can not be absorbed by the bowels: -bacteria, viruses may effect ion channels which mean water potential causes water to leave the blood and enter in lumen and not be absorbed.
31
how many layers does the GI tract have
4 layers
32
4 layers of the GI tract
mucosa sub mucosa muscular propria adventitia
33
3 layers of mucosa
1. lining of epithelium (including glandular tissue) 2. lamina propria (vascularised loose connective tissue) 3. muscular mucosal (thin layer of smooth muscle)
34
sub mucose
loose connective layer--> large blood vessels, lymphatics, nerves and muscuos secreting glands
35
muscular propria (2 layers)
inner layer is circular outer layer is longitudinal --> for peristalsis
36
adventitia
outer most layer - loos connective tissue, covered by visceral peritoneum - blood vessels lymphatics and nerves
37
mucosa folds into deep pits
1) enzymes (acids from pits) | 2) mucus from necks
38
4 types of cells within gastric pits
mucous secreting surface and neck cells parietal cells chief cells g cells D cells
39
parietal cells
HCL and intrinsic factors (FUNDUS)
40
chief cells
pepsinogen (FUNDUS)
41
G cells
gastrin (ANTRUM)
42
D cells
somatostatin (ANTRUM)
43
production of stomach acid
(first all receptors must be full on outside of parietal cell- histamine, AcH, CCK) - co2 enters parietal cell form blood forming H2CO3 with water - H2CO3 dissociate to form H+ and HCO3- - H+ (ATP dependent pump) pumps out H+ into the gastric lumen and K+ are pumped in, in exchanged - HCO3- is pumped out into the blood and Cl- is pumped in - cl- passively diffuses out, as well as K+ - Cl- and H+ covalently bond in the lumen to form HCL
44
control of HCL production
- -distension protein attaches to G cell, this causes GASTRIN to be released - GASTRIN causes 2 responses: stimulates paras NS to release AcH (which attaches to receptor on parietal cell membrane). It also causes the blood to release CCK which causes ECL cells to release histamine. Then both histamine and CCK attach to their receptors on the parietal cells. - when all receptors are full this triggers CO2 to enter the cell and production of HCL is started.
45
uses of HCL
-kills bacteria -denatures proteins helps gastric lipase -converts pepsinogen to pepsin
46
regulation (3)
cephalic gastric intestinal
47
mucus cells secrete a protective coat of
bicarbonate mucus- alkaline
48
what mark the entry of gastric glands
gastric pits
49
cells found in funds and body which produce most gastric secretions
parietal, chief, mucous neck cells, enteroendocrine (G cells
50
what is released in pyloric antrum
gastrin and mucus
51
parietal cells
HCL and intrinsic factor
52
hcl
denatures proteins, kills bacteria, needed to activate pepsin
53
chief cells
secrete pepsinogen --> the inactive version of pepsin
54
pepsin is activated by
HCL released by parietal cells
55
mucous neck cells
thin, acidic mucus ---> diff from mucous secreted by goblet cells
56
G cells (enteroendocrine)
gastrin
57
gastrin
promotes gastric emptying and increases secretion by gastric glands
58
histamine
stimulates parietal cells to release HCL
59
cephalic phase
sight/smell of food, causes the vagus nerve to be stimulated and therefore and increase in gastric motility
60
gastric phase
stomach distention causes local reflexes and vagovagel reflexes which stimulates the vagus nerve. Food chemicals increase the pH and activates chemoreceptors--> G cell secretion of gastrin. Stimulates stomach secretory activity
61
intestinal phase
low pH and partially digested food in duodenum. stomach empties and increase in intestinal gastrin
62
enteric
controls sooth muscle contraction and G1 secretions and blood flow
63
autonomic
parasympathetic -vagus nerve--> rest and digest | sympathetic --> fight or flight
64
pancreas
chief factory for digestive enzymes that are secreted into the duodenum e..g proteases, lipase, carbohydrases
65
liver
produces and secretes bile
66
gall bladder
storage of bile
67
bile
helps absorb fats --> emulsification. carries waste from the liver which cannot go through the kidney
68
mouth, stomach, s.intestine
mouth--> amylase stomach--> protease s.intestine --> amylase, protease, lipases
69
protein molecules get broken down into
amino acid molecules
70
liver and gall bladder secretes
``` bile phospholipids bicarbonate ions cholesterol bile pigments ```
71
pernicious anaemia
caused by impaired absorption of B12 within the s.intestine - -> malabsorption - -> atrophic gastritis - -> intestinal disease - -> acid suppressant
72
B12 needed for
nervous system function and red blood cell formation
73
what is needed for b12 absorption
intrinsic factor released by parietal cells
74
bad cholesterol
low density lipoprotein
75
LDL
makes up the majority of the bodies cholesterol. having high levels can lead to plaque build-up in your arteries and result in heart disease and strokes
76
HDL
good cholesterol--> absorbs cholesterol and takes