Physiology of Large Intestine Flashcards

1
Q

Longitudinal muscle in caecum and colon divided into 3 strands called

A

taeniae coli

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

Longitudinal muscle encircles what

A

anus and rectum

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

Where does smooth muscle become thickened

A

internal anal sphincter

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

skeletal muscle encircles what

A

external anal sphincter

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

Taeniae coli and circular muscle create

A

Haustra

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

What comes from taeniae coli

A

Appendices

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the caecum receive

A

1-2l of undigested material, unabsorbed fluid, unabsorbed biliary contents from the terminal ileum via ileocaecal valve

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

What stimulates the opening of the ileoecaecal valve

A

CCK and gastrin

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

The gastroileal reflex is influenced by

A

distention of the stomach –> open
distention of the ascending colon –> close
hormones, parasympathetic, sympathetic, enteric neurones

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

What is the appendix

A

Blind ended tube with extensive lymphoid tissue

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

How does the appendix attach to the caecum

A

via appendicael orofice

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

What may cause the appendix to become obstructed leading to appendicitis

A

faecalith

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

Primary functions of colon

A

Absorption of sodium, calcium, water = condenses ileoceacal material into solid/semi-solid stool
Fermentes undigested carbohydrates into short chain fatty acids by colonic material
Secretions K, HCO3 and mucus
Reservoir - storage
Periodic elimination of faeces

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

Fluid reabsorption and bacterial elimination occurs till

A

Distal end of transverse colon

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

Final drying and storage

A

Descending colon and rectum

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

Periodic elimination of faeces is voluntary or involuntarty

A

Usually voluntary after early childhood

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

WHat is faeces made up of

A
100g/100ml = H20
50g = bilirubin, little salt, bacteria, cellulose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

mucosa of the large intestine lacks what

A

villi

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

Mucosa of the small intestine possesses

A

circular folds, crypts and microvilli which increase SA

20
Q

Surface epithelial colonocytes

A

mediate electrolyte absorption

osmosis driven by H2O absorption

21
Q

Crypts

A

ion secretion

22
Q

Goblet cells

A

Mucus

Protein defense

23
Q

Na/K absorption increased by

A

aldosterone

24
Q

significant loss of what in faeces in secretory diarrhoea

A

Potassium

25
Q

Haustration

A

non propulsive movement alternating contraction to circular muscle

26
Q

When do haustra appear and disappear

A

Appear after mass movement

27
Q

How often does haustration occur

A

very slowly between 16 and 48 hours to allow for absorption

28
Q

A mass movement involves

A

large secretions of circular and transverse colon powerfully drives faeces into distal region

29
Q

A mass movement occurs

A

1-3 times per day

30
Q

What is a mass movement normally stimulated by

A

Gastroileal response after a meal

31
Q

Mass movement in distal region propels faces into what

A

Rectum

32
Q

In a mass movement the rectum fills with faeces. What does this activate

A

Faecal stretch receptors

33
Q

Contraction of the smooth muscle of sigmoid colon and rectum (internal anal sphincter) can cause

A

Relaxation of skeletal muscle of external anal sphincter = ASSITS DEFECATION
Contraction of skeletal muscle of external anal sphincter = DELAYED DEFECATION

34
Q

The colon contains about 500-1000 bacteria the most are beneficial to the gut what are their main functions

A

Increase intestinal immunity
Promote motility
Synthesise vit K2 and free fatty acids
activate some IBD treatment

35
Q

As well as faeces what else does the anus permit expulsion of

A

Intestinal gas - flatus

36
Q

Flatus is a result of

A

swallowed air
some carbohydrates require certain bacteria to be absorbed
internal and external anal sphincters contract and leave. a narrow exit which doesn’t permit solid matter to pass through

37
Q

How does Irritable Bowel Syndrome Present

A

bouts of diarrhoea, constipation and abdo pain

38
Q

What is the treatment of Irritable Bowel Syndrome

A

modification of diet
anti-diarrhoeals
anti-spasmodics
laxatives

39
Q

Explain the use of linaclotide

A

Peptide drug used for the treatment of moderate to severe IBS with constipation in adults

40
Q

How does linaclotide work

A

Increases secretion of Chloride and bicarbonate

Increases intestinal transmit

41
Q

What is the benefit of linaclotide

A

Improves bowel movement and alleviates discomfort

42
Q

What are the side effects of linaclotide

A

diarrhoea

43
Q

Unlicensed low doses of amitriptyline are used for

A

Abdo pain

44
Q

Inflammatory Bowel Disease is an overarching term for

A

Crohn’s - Entire gut

UC - Colon

45
Q

Acute IBD treatment

A

Glucocorticoids e.g. prednisolone

Prolonged use –> adrenal suppression

46
Q

Aminosalicylcates include

A

Sulfasalazine

47
Q

Aminosalicylates are used to

A

Decrease inflammation in maintenance and mild UC