Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

(SALMA) Physiology > GI > Flashcards

GI Flashcards

1
Q

what is the foregut

A

lower end of hypopharynx - 1/3 down duodenum

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

what is the midgut

A

1/3 down duodenum - 2/3 along transverse colon

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

what is the hindgut

A

2/3 way along transverse colon - anal canal

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

which embryological part is the liver, biliary apparatus, pancreas etc located in

A

foregut

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

what is the arterial n nerve supply of foregut

A

coeliac trunk

- greater splanchnic nerve (T6-9)

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

what is the arterial n nerve supply of midgut

A

sup mesenteric artery

- lesser splanchnic nerve (T10-11)

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

what is the arterial n nerve supply of hindgut

A

inf mesenteric artery

- least splahnic nerve (t12-l1)

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

what is swallowing initiated by

A

pressure receptors in pharynx walls stimulated

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

what is the diff btwn proximal 1/3 of oesophagus and distal 1/3

A

striated muscle
vs
smooth muscle

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

what are the 3 stages of swallowing

A

1 - voluntary (food compressed against much roof, pushed to oropharynx by tongue)

2 - involuntary (nasopharynx closed by soft palate, pharynx shortened n widened, hyoid elevates, epiglottis closes trachea)

3 - involuntary (contraction of constrictor muscles followed by depression of hyoid bone n pharynx, bolus pushed to oesophagus)

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

which muscles manipulate food during chewing n elevate hyoid bone/flatten floor of mouth during s1

A

buccinators

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

in s2, what is the pharynx shortened n widened by

A

elevation of hyoid bone (via actions of muscles of the floor of the palate)

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

what raises the larynx n closes glottis to prevent food from entering trachea

A

swallowing centre

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

how many seconds does it take 1 oesophageal peristaltic wave to reach stomach

A

9 seconds

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

what is the upper oesophageal sphincter

A

ring of skeletal muscle surrounds oesophagus jus below pharynx

  • before food enters oesophagus, immediately after food has passed, sphincter closes, glottis opens n breathing resumes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the gag reflex

A

reflex elevation of pharynx

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

what are true vocal cords

A

vocal folds

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

what are false vocal cords

A

vestibular folds

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

name some properties of saliva

A
  • lubricant for mastication, speech etc
  • oral hygiene, maintains pH around 7.2
  • release digestive enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

which glands secrete serous

A

patotid

submandibular n sublingual secrete serous and mucous

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

which glands secrete mucous

A

minor glands

submandibular n sublingual do both

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

what is diff btwn mucous and serous secretion

A

mucous - mucins for lubricant of mucosa

serous - alpha amylase for starch digestion

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

what are 3 components of defence of oral cavity

A 
mucosa (physical)
salivary glands (washes away)
palatine tonsils (surveillance system for immune system)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is structural of salivary glands

A

2 diff types of epithelia:

  • acinar cells (functional unit)
  • ducts (surrounded by acinar cells - have channels enabling transport of fluid etc)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are interlobular duct divided into

A

intercalated (connect acini to larger striated ducts) n striated (major site of reabsorption of NaCl)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

where are some minor salivary glands located

A

lips, cheeks, hard/soft palate etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

which strucs pass through parotid gland

A

external carotid artery
facial nerve CN VII

thus, parotid capsule is very tough

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is PS innervation of the 3 major salivary glands

A

parotid - CN IX glossopharyngeal

submandibular/sublingual - CN VII facial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

list some functions of the stomach

A
  • store/mix food
  • digestion
  • kill microbes
  • secrete intrinsic factor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

name the 5 main diff stomach cells

A
  1. parietal cells
  2. chief cells
  3. g cells
  4. ecl cells
  5. d cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what do parietal cells secrete

A

HCl/gastric acid

intrinsic factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what do chief cells secrete

A

pepsinogen

gastric lipase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what do g cells secrte

A

gastrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what do ecl cells secrete

A

histamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what do d cells secrete

A

somatostatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what is the role of parietal cells (hcl, instrinc factor)

A
  • kill microbes
  • activate pepsinogen
  • intrinsic factor binds to vit B12
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is the role of chief cells (pepsinogen, gastric lipase)

A

protein and fat digestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what is the role of G cells (gastrin) and ECL cells (histamine)

A

stimulate gastric acid secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is the role of D cells (somatostatin)

A

inhibits gastric acids ecretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what stimulates and inhibits gastric acid secretion

A

stimulates - G cells (gastrin) and ECL cells (histamine)

inhibits - D cells (somatostatin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what does ECL stand for

A

enterochromaffin-like cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what is gastric acid

A

mainly HCl, pH 2
energy dependant
neurohormonal reg
from parietal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

how is gastric acids secreted/prod (4)

A
  1. H2O in parietal cells break down –> OH- & H+
  2. H+ pumped into stomach via H+/K+ ATPase pumps in membrane of parietal cells (1K+ into parietal cell for every 1H+ pumped out of stomach)
  3. HCO3- from H2CO3 breakdown secreted into capillary for exchange of Cl-
  4. In stomach, H+ and Cl- react to form HCl
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

how is gastric acid secretion regulated initially

A

turning it on (cephalic phase)

  • PS NS
  • sight, smell triggers
  • ACh triggers gastrin release (from G cells) and histamine (from ECL cells)
  • Both of these incr number of H+/K+ ATPase pumps on parietal cell

thus increased acid production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what happens once food has reached stomach (in terms of gastric acid secretion)

A

turning it on (gastric phase)

  • initiated by gastric distension
  • same things happen as cephalic phase (gastrin n histamine release, incr pumps, incr acid production)
46
Q

how do proteins in the stomach stimulate gastric acid release

A

direct stimulus

  • proteins in lumen act as buffer, cause pH to rise
  • less secretion of somatostatin - more acid produced
47
Q

how is gastric acid secretion turned off (gastric phase)

A

gastric phase

  • low luminal pH directly inhibits gastrin secretion
  • stimulates somatostatin release - inhibits parietal cell activity
48
Q

how is gastric acid secretion turned off (intestinal phase)

A 
in duodenum:
- duodenal distension
- low luminal pH
- presence of amino acids
- release of enterogastrones 
eg CCK - reduces ACh release
and secretin which reduces gastrin release n incr somatostatin release
49
Q

what 3 factors help regulate gastric acid secretion

A

brain
duodenum
stomach

50
Q

which PS neurotransmitter is involved in gastric acid reg

A

ACh - turning it on, cephalic phase

51
Q

what are peptic ulcers

A

breach in mucosal surfce

52
Q

how does gastric mucosa defend itself

A
  • alkaline mucus (lie on gastric pit surface)
  • tight junctions btwn epithelial cells
  • replacement of damaged cells
53
Q

how does ammonia affect gastric mucosa

A

toxic, less mucous produced

54
Q

what does the secretion of pepsinogen parallel

A

HCl secretion

55
Q

what are the 3 steps of protease secretion

A
  1. chief cells secrete pepsinogen
  2. pepsinogen converted to pepsin in stomach lumen - low pH
  3. speeds up protein digestion - neutralised by bicarb in duodenum
56
Q

what is the role of pepsin in protein digestion

A
  • not essential but no vit B12 can occur

- accelerates protein digestion

57
Q

what is vol of empty stomach

A

50mL

58
Q

what is vol of stomach when eating

A

1.5L

59
Q

the smooth muscle in the stomach undergoes receptive relaxation - what do this mean

A

reflex in which the gastric fundus dilates when food passes down the pharynx and the esophagus

60
Q

what is receptive relaxation is mediated by

A

PNS
with co-ord from stomach by Vagal nerve n brain’s swallowing centre

Vagus nerve causes NO n serotonin release

61
Q

where do peristaltic waves begin

A

in the body of the stomach - prod a ripple as it proceeds towards antrum

62
Q

what does the pyloric sphincter do as peristaltic waves reach it

A

close

63
Q

what is pyloric sphincter

A

ring of smooth muscle n connective tissue btwn atrium n duodenum

64
Q

what is the freq of peristaltic waves detrained by

A

pacemaker cells in muscular propria of fundus undergo slow depolarisaiton-repolarisation cycles (3/min)

65
Q

what can increase strength of peristaltic waves

A

gastrin

gastric distension

66
Q

what can decrease strength of peristaltic waves

A

duodenal distension
incr duodenal fat
incr duodenal osmolarity

67
Q

what is the most abundance substance in chyme

A

water

68
Q

which part of s intestine reabsorbs most water

A

jejunum

69
Q

what is the most abundant solute in chyme

A

Na+

70
Q

how can diarrhoea affect K+ levels

A

decreases

71
Q

what are the 2 functional states the body undergoes in providing energy for cellular activities

A
  1. absorptive state:
    - ingested nutrients enter blood from GI tract
    - some nutrients provide energy requirements of body remainder added to body’s energy stores to be called upon in the next postabsorptive state
  2. post absorptive state:
    GI tract empty of nutrients
    body’s own supply must store energy
72
Q

does the brain store glucose

A

no

73
Q

how are excess triglycerides stored

A

adipose tissue

74
Q

how is excess glycogen stored

A

in liver and muscle

75
Q

what process happens in a short fast

A

glycogenolysis

76
Q

what process happens in a long fast

A

gluconeogenesis

77
Q

what is a fuel source of muscles

A

ketones

78
Q

what is the process of breaking down triglyceride stores

A

lipolysis

79
Q

what is lipolysis promoted by

A

glucagon

80
Q

what happens when body goes into starvation state (4-5 days)

A

muscles use less ketones - needed for brain
liver can’t make new glucose
brain relies on ketones so glucose is available for rbc

81
Q

what is diff btwn ghrelin n leptin

A

ghrelin is hunger hormone whereas leptin suppresses hunger

82
Q

in obesity, would leptin or gremlin levels be high

A

leptin (leptin resistance may also occur)

83
Q

which hormones are involved in metabolism control

A

insulin is anabolic

the rest are catabolic

84
Q

what is the most abundant fatty acid absorbed

A

palmitic acid

85
Q

where is lipase synthesised

A

pancreas

86
Q

what do triglycerides split into

A

monoglyceride n 2 fatty acids

87
Q

what do serous acini secrete

A

water n amylase

88
Q

what do mucous acini secrete

A

mucous

89
Q

what is the diff btwn primary n mature saliva

A

primary - high in NaCl

mature - high in KCO3

90
Q

what is the BMR

A

rate of energy expenditure in body for vital processes at rest (related to ATP use, measured by oxygen consumption)

91
Q

what are the energy requirements of brain

A

glucose

ketone bodies

92
Q

what are the energy requirements of liver

A

amino aicds
fatty acids
glucose
alcohol

93
Q

what are the energy requirements of muscles

A

glucose
triglycerides
amino acids

94
Q

what are the energy requirements of rbc

A

glucose

95
Q

what is vit A involved in

A

immune system

vision

96
Q

what is vit B involved in

A

RBC prod

97
Q

what is vit C involved in

A

collagen prod

haemostasis

98
Q

what is vit D involved in

A

bone formation n maintenace

99
Q

what is vit E involved in

A

free radical protection

100
Q

what is vit K involved in

A

blood clotting

101
Q

what are the 3 phases of gastric acid secetion

A
  1. cephalic phase
  2. gastric phase
  3. duodenal phase
102
Q

what are the 4 steps of water absorption

A
  1. Na absorbed (cotransported) by enterocytes
  2. Na/K pump transports 3Na out and 2K in (electrochemical grad)
  3. high intercellular Na conc, low intracellular conc
  4. water diffuses into enterocytes through aquaporins
103
Q

where is iron absorbed

A

duodenum

104
Q

what does the jejunum absorb

A

most other vitamins

105
Q

what does ileum absorb

A

b12 n bile salts

106
Q

what are the steps of carb digestion n absorption

A
  1. pancreatic n salivary amylase break down poly –> disaccharides
  2. maltase, sucrose, lactase etc cleave di –> monosaccharides
  3. sodium binds to hexose transporter
  4. glucose binds - glucose n Na invaginated into enterocyte
  5. hexose transporter on basolateral membrane transports monosaccharides into capillaries down conc gradient
107
Q

what are enterocytes

A

intestinal absorptive cells

108
Q

what does an amino acid consist of

A

central C atom
NH2, COOH, H group
variable R group
forms zwitterions - H from COOH moves to NH2

109
Q

4 structure of proteins?

A

1 - aa sequence
2 - alpha helix n beta pleated sheet
3- disulphide bridges, polar interactions, hydrogen bonding
4- multiple tertiary structures

110
Q

what are the 5 steps of protein digestion n absorption

A
  1. dietary proteins broken down by pepsin (stomach) n proteases (pancreas) –> polypeptides
  2. polypeptides broken down by peptidases in villi of enterocyte - amino acids
  3. sodium binds to sodium dependant amino acid transporters –> aa bind
  4. transporter undergoes conformational change - aa and Na enter cell
  5. aa transported into blood via basolateral membrane transporter
111
Q

what are the 5 steps of lipid digestion and absorption

A
  1. pancreatic lipase breaks down triglycerides –> glycerol n 3 date acids
  2. bile salts emulsify fats - micelles absorbed by enterocytes
  3. triglycerides + cholesterol + lipoproteins = chylomicrons
  4. chylomicrons transported into lymphatic system
  5. lipoprotein lipase oxidises triglycerides - used for energy or storage
112
Q

what is the equation for BMI

A

weight in kg/height in m^2

(SALMA) Physiology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions