Metabolism Flashcards Preview

1 - FINALS > Metabolism > Flashcards

Flashcards in Metabolism Deck (143):
1

Where does the parotid gland open out?

Opposite the second upper molar

2

Where does the submandibular gland open out?

Either side of the frenulum

3

Where does the sublingual gland open out?

Plica sublingualis - fold between tongue and body of the mandible

4

Nerve supply to the parotid gland

Via auriculo-temporal nerve
Sensory fibres from V3
Parasympathetic fibres from the lesser petrosal nerve from CN IX

5

Nerve supply to the submandibular and sublingual glands

Chorda tympani

6

Derivatives of body and root of the tongue

Body = ectoderm
Root = endoderm

7

4 extrinsic muscles of the tongue and their innervation

Styloglossus - CN XII - to styloid process
Genioglossus - CN XII - to mandible
Palatoglossus - CN X - to palate
Hypoglossus - CN XII - to hyoid bone

8

Nerve supply to the anterior 2/3 of the tongue

General sensory = V3
Special sensory = CN VII

9

Nerve supply to posterior 1/3 of the tongue

General and special sensory = Cn IX
Patch at the root = internal laryngeal CN X

10

Pharyngeal constrictor muscles

Superior - from medial pterygoid plate
Middle - from angle between hyoid horns
Inferior - from lateral thyroid cartilage

11

Muscles of mastication and actions

Temporalis - closes mouth
Masseter - closes mouth
Medial pterygoid - closes mouth
Lateral pterygoid - opens mouth

12

Innervation of muscles of mastication

V3

13

Extent of oesophagus

C6-->T10

14

What muscle is found around the UOS

Cricopharyngeal

15

Sites of oesophageal constrictions

In the pharynx
Behind aortic arch
Diaphragmatic

16

3 layers of stomach muscle

Inner oblique
Middle circular
Outer longitudinal

17

4 parts of duodenum

Superior
Descending
Horizontal
Ascending

18

Jejunum vs ileum

Jejunum darker
Jejunum more vascular
Jejunum more folds
Jejunum thicker walls
Jejunum less fat

19

Quantity of jejunum vs iluem

Jejunum = 2/5 of gut
Ileum = 3/5

20

Where is the bare area of the liver?

Superior and posterior surfaces

21

Arterial arcades in jejunum vs iluem

Longer but fewer in jejunum
More but shorter in ileum

22

Portal venous system

Splenic and inferior mesenteric veins join
Then join superior mesenteric vein
Forms hepatic portal vein

23

Coeliac trunk branches

Left gastric
Splenic
Common hepatic

24

Splenic artery branches

Left gastroepiploic
Short gastrics

25

Common hepatic artery branches

Hepatic artery proper --> left and right hepatic, cystic, right gastric
Gastroduodenal --> right gastroepiploic, superior pancreaticoduodenal

26

Superior mesenteric artery branches

Jejunal and ileal
Iliocolic
Right colic
Middle colic

27

Inferior mesenteric artery branches

Left colic
Sigmoidal
Superior rectal

28

Falciform ligament

Anterior abdominal wall --> liver

29

Lesser omentum

Liver --> lesser curvature of the stomach

30

Greater omentum

Greater curvature of the stomach --> transverse colon

31

Transverse mesocolon

Transverse colon --> posterior body wall

32

Mesentery

Small intestine --> posterior body wall

33

Immune systems in the gut

MALT
Secretory IgA

34

Gut layers

Mucosa
Submucosa
Muscularis propria
Adventitia

35

Oesophageal epithelium

Stratified squamous

36

What is secreted by the cardia of the stomach?

Mainly mucous from mucous neck cells

37

What is secreted by the fundus of the stomach?

Mucous from mucous neck cells
HCL and intrinsic factor from parietal cells
Pepsin from chief cells
Gut hormones from endocrine cells

38

What is secreted by the pylorus of the stomach?

Mainly mucous from mucous neck cells
Gut hormones from endocrine cells

39

Cells of intestinal crypts

Enterocyte - secretion of watery intestinal juice
Endocrine cell - regulation of gut function
Stem cell - regeneration of epithelium
Paneth cell - antimicrobial agent release such as lysozyme

40

Where are Peyer's patches found?

Lamina propria of the ileum

41

What are taenia coli?

Bands of longitudinal muscle in the colon

42

Where are Brunner's glands found?

Submucosa of the duodenum

43

Brunner's gland function

Alkaline mucous secretion for neutralisation of acidic chyme

44

Which enzyme has a calmodulin subunit that is activated during enzyme and what is its function?

Phosphorylase kinase A
Phosphorylated glycogen phosphatase
Activates glycogen breakdown

45

What does calcium activate during exercise?

PDC phosphatase to activate PDC to promote entry in TCA cycle
Dehydrogenase enzymes of the TCA cycle

46

What does AMP do in exercise?

Increases GLUT4 channels
Enzymes at the start of glycolysis
Glycogen phosphorylase
AMPK which turns on PFK2
Inactivates ACC to prevent malonyl CoA formation which would inhibit fatty acid breakdown for energy

47

What is hormone sensitive lipase controlled by?

Promoted by glucagon and adrenaline
Inhibited by insulin

48

Process of fatty acid breakdown

Activation by ATP to form fatty acyl CoA
Transport into mitochondria via carnitine shuttle
Beta oxidation to produce acetyl CoA, NADH and FADH2

49

How is CPT1 (carnitine shuttle) controlled?

Promoted by cAMP and glucagon
Inhibited by malonyl CoA

50

Lipogenesis steps

Formation of malonyl CoA by acetyl CoA carboxylase
Fatty acid synthetase adding 2 carbons at a time

51

Ketone body formation

acetyl CoA --> acetoacetyl CoA --> HMG CoA --> acetoacetate

52

Effect on insulin on ketone body production

Insulin inhibits ketone body production by inhibiting HSL and CPTI
Ketoacidosis common in diabetics

53

What enzyme is used to overcome glucokinase?

Glucose-6-phosphatase

54

What enzyme is used to overcome PFK?

Fructuse-1,6-phosphatase

55

What enzyme is used to overcome pyruvate kinase?

Pyruvate carboxylase
Malate dehydrogenase
PEP carboxykinase

56

Where does glycerol enter respiration?

Dihydroxyacetone phosphate in glycolysis

57

Where does glutamine/glutamate enter the TCA cycle?

As a-ketoglutarate

58

Hows does alanine enter respiration?

Converted to pyruvate

59

Primer for glycogen synthesis

Glycogenin - modified tyrosine

60

Von Giurke's disease

Type I glucogen storage disease
Deficiency of glucose-6-phophatase
Glucose from glycogolysis or gluconeogenesis cannot be exported from the liver
Hypoglycaemia and lactic acidaemia

61

McArdle's disease

Type 5 glycogen storage disease
Deficiency of muscle phosphorylase
Exercise induced fatigue and cramps

62

Her's disease

Type 6 glycogen storage disease
Deficiency of liver phosphorylase
Hypoglycaemia

63

GLUT transporters

GLUT1 - constitutive
GLUT2 - liver and pancreas
GLUT4 - muscle and adipose tissue - controlled by insulin

64

Hexokinase

Sensitive to feedback inhibition
Wide specificity

65

Glucokinase

Only in liver and pancreas
Specific to glucose
Not sensitive to feedback inhibition

66

PFK1 control

Promoted by F2,6P2
Indreictly promoted by high ADP and AMP levels
Inhibited by citrate, high ATP

67

Where does fructose enter glycolysis?

As fructose-6-phosphate
Converted by hexokinase or fructokinase

68

What do chylomicrons carry?

Dietary TAGs

69

What do VLDLs carry?

Liver derived TAGs

70

What do IDLs carry?

TAGs and cholesterol

71

What do LDLs carry?

Cholesterol

72

What do HDLs carry?

Reverse cholesterol transport

73

Where is apoB48 found?

Chylomicrons

74

Where is apoB100 found?

VLDLs, IDL, LDLs

75

What does apoE do?

Controls receptor binding of remnant particles

76

What does apoC do?

Acts as an enzyme inhibitor of lipoprotein lipase

77

What apoproteins do chylomicrons contain?

B48, A, C, E

78

What apoproteins do VLDLs contain?

B100, A, C, E

79

What apoproteins do IDLs contain?

B100, E

80

What apoproteins do LDLs contain?

B100

81

What apoproteins do HDLs contain?

AI, AII, C, E

82

Galactose intolerance

Deficiency of galactose-1-phosphate uridyl transferase
Galactose cannot be converted to glucose in the liver
Accumulation of galactose

83

Fructose intolerance

Fructose aldolase deficiency

84

PKU

Deficiency of phenylalanine hydroxylase
No conversion to tyrosine

85

Maple syrup urine disease

Unable to break down branched amino acids
Build up of keto acids
Sweet urine

86

MCADD

Can't break down medium or long chain fatty acids

87

Familial hypercholesterolaemia

Reduced number of functional LDL receptors
More LDL in circulation so more cholesterol deposition

88

What is tyrosine used to make?

Melanin, dopamine, adrenaline, noradrenaline, thyroxine

89

What is tryptophan used to make?

Serotonin, melatonin

90

What is arginine used to make?

Nitric oxide

91

What is histadine used to make?

Histamine

92

What can alanine be converted to by transamination?

Pyruvate

93

What can glutamate be converted to by transamination?

a-ketoglutarate

94

What can aspartate be converted to by transamination?

Oxaloacetate

95

Urea cycle

CO2 + NH4 + ornithine
Cabamoyl phosphate
Citrulline
Arginosuccinate
Arginine
Urea + ornithine

96

Control of PDC

Controlled by feedback inhibition from acetyl CoA and NADH

97

ETC complex I

NADH --> UQ

98

ETC complex II

FADH2 --> UQ
Unable to pump proton into IM space

99

ETC complex II

UQ --> cytochrome C

100

ETC complex IV

Cytochrome C --> oxygen

101

What do carbon monoxide and cyanide inhibit?

Complex IV - cytochrome C oxidase

102

Natural antibiotics that can uncouple?

Gramicidin
Nigericin
Valinomycin

103

What does dinitrophenol do?

Can carry H+ ions across membrane
Avoids ATP synthase

104

What happens to HIF-1 in hypoxia

Beta subunit stabilised
Can bind to regulatory sections of genes
Promotes gene transcription of genes involved in glycogen breakdown and glycolysis
Induces transcription of EPO and VEGF
Promotes mitochondrial autophagy and suppresses fission

105

Difference in saliva secretions from glands

Parotid = serous and rich in amylase
SubML = serous and mucous rich in proline rich proteins

106

Control of salivary secretions

M3 receptors
Vasoactive intestinal protein

107

Function of intrinsic factor

Critical for vitamin B12 absorption

108

Where is gastrin secreted from?

G cells in the antrum

109

Where is somatostatin secreted from?

D cells in the antrum

110

What is the action of gastrin

Stimulates parietal cells to secrete acid via CCKB receptors
Stimulates ECL cells to release histamine which stimulates parietal cells via H2 receptors

111

When is somatostatin released and what does it do?

Released in presence of acid
Inhibits G cells, ECL cells and parietal cells

112

Where is secretin produced

S cells of the duodenum

113

What stimulates pepsin release?

Gastrin from G cells
Secretin from duodenal S cells
ACh via M3 receptor
Acid is gastric mucosa

114

What cleaves pepsinogen to pepsin?

Acid and pepsin

115

What promotes pancreatic secretions?

VIP and secretin promote secretion of aqueous component
CCK promotes secretion of enzymatic content

116

Where is CCK released from and when?

From duodenal I cells
In response to fat and peptide presence

117

Pancreatic zymogens

Trypsinogen
Chymotrypsinogen
Procarboxypeptidase
Proelastase

118

What converts trypsinogen?

Enteropeptidase

119

Active pancreatic enzymes

Glycerol ester hydrolase
Cholesterol ester hydrolase
Phospholipase A2

120

Bile salts

Synthesised from cholic acid originally from cholesterol

121

What stimulates bile release?

CCK, ACh, gastrin

122

Effect of secretin on bile?

Stimulates bicarbonate and water release into bile

123

Lipid absorption

Form micelles than can diffuse through membrane
Remade into TAGs by smooth ER
Packaged into chylomicrons
Secreted into IC space
Taken up by lacteals and join lymphatic circulation

124

Components of saliva

Amylase
Lysozyme
Bicarbonate
Growth factors
Transcoblamin II

125

Gastric secretions

Mucous
Acid
Proteases
Lipase
Intrinsic factor

126

Gastric acid secretion

Carbon dioxide in
Converted to bicarbonate and protons by CA
Bicarbonate pumped out into plasma and exchnaged for Cl-
H+ pumped out by H+/K+ ATPase
Cl- and K+ pumped out into lumen

127

How H2 receptor activation leads to gastric acid secretion

Activates adenylyl cyclase
ATP --> cAMP
Activates protein kinase
Activates H+/K+ ATPase

128

Interstitial cells of Cajal

Create rhythm of electrical slow waves
Cause phasic contractions

129

Migrating motor complexes

3 phases every 90-120 minutes
Create sensation of hunger
Clear undigested material
Prevent bacterial overgrowth

130

Cephalic phase

Triggered by sight, smell, taste of food
Prepares GI tract by stimulating gastric, salivary, pancreatic and gastrin secretions

131

Gastric phase

Triggered by stomach distension
Stimulates gastric acid secretion

132

Intestinal phase

Triggered by chemoreceptor activation in the small bowel
Inhibits further gastric secretions

133

Waves of peristalsis in the oesophagus

Primary = occurs on swallowing
Secondary = pushes bolus into stomach

134

Graph of liquid gastric emptying

Exponential

135

Graph of solids gastric emptying

Lag period
Then linear

136

Duodenal and jejunal brake

HCl, LCFAs, AAs, glucose, peptides in these regions
Reduces pyloric sphincter opening
Reduces antral contraction
Enhanced relaxation and storage of fundus

137

Ileal brake

Peptide YY, GLP-1, oxntomodulin
Fats in ileum
Slows gastric emptying and induces satiety

138

Vomiting centre

Nucleus of the solitary tract
Dorsal motor nucleus of vagus

139

What communicates with the vomiting centre?

Area postrema

140

Motion type anti-emetics

Muscarinic antagonists - hyoscine

141

Old type anti-emetics

D2 receptor antagonists - act on area postrema to block vomiting induced by blood borne agents
H1 receptor antagonists
Cannabinoid derivatives

142

New type anti-emetics

5-HT3 receptor antagonists
NK1 receptor antagonists

143

Corticosteroids as anti-emetics

Anti-inflammatory
Enhances anti-emetic effects of other drugs
Anti-nausea effects