Metabolism Flashcards
(143 cards)
1
Q
Where does the parotid gland open out?
A
Opposite the second upper molar
2
Q
Where does the submandibular gland open out?
A
Either side of the frenulum
3
Q
Where does the sublingual gland open out?
A
Plica sublingualis - fold between tongue and body of the mandible
4
Q
Nerve supply to the parotid gland
A
Via auriculo-temporal nerve
Sensory fibres from V3
Parasympathetic fibres from the lesser petrosal nerve from CN IX
5
Q
Nerve supply to the submandibular and sublingual glands
A
Chorda tympani
6
Q
Derivatives of body and root of the tongue
A
Body = ectoderm Root = endoderm
7
Q
4 extrinsic muscles of the tongue and their innervation
A
Styloglossus - CN XII - to styloid process
Genioglossus - CN XII - to mandible
Palatoglossus - CN X - to palate
Hypoglossus - CN XII - to hyoid bone
8
Q
Nerve supply to the anterior 2/3 of the tongue
A
General sensory = V3
Special sensory = CN VII
9
Q
Nerve supply to posterior 1/3 of the tongue
A
General and special sensory = Cn IX
Patch at the root = internal laryngeal CN X
10
Q
Pharyngeal constrictor muscles
A
Superior - from medial pterygoid plate
Middle - from angle between hyoid horns
Inferior - from lateral thyroid cartilage
11
Q
Muscles of mastication and actions
A
Temporalis - closes mouth
Masseter - closes mouth
Medial pterygoid - closes mouth
Lateral pterygoid - opens mouth
12
Q
Innervation of muscles of mastication
A
V3
13
Q
Extent of oesophagus
A
C6–>T10
14
Q
What muscle is found around the UOS
A
Cricopharyngeal
15
Q
Sites of oesophageal constrictions
A
In the pharynx
Behind aortic arch
Diaphragmatic
16
Q
3 layers of stomach muscle
A
Inner oblique
Middle circular
Outer longitudinal
17
Q
4 parts of duodenum
A
Superior
Descending
Horizontal
Ascending
18
Q
Jejunum vs ileum
A
Jejunum darker Jejunum more vascular Jejunum more folds Jejunum thicker walls Jejunum less fat
19
Q
Quantity of jejunum vs iluem
A
Jejunum = 2/5 of gut Ileum = 3/5
20
Q
Where is the bare area of the liver?
A
Superior and posterior surfaces
21
Q
Arterial arcades in jejunum vs iluem
A
Longer but fewer in jejunum
More but shorter in ileum
22
Q
Portal venous system
A
Splenic and inferior mesenteric veins join
Then join superior mesenteric vein
Forms hepatic portal vein
23
Q
Coeliac trunk branches
A
Left gastric
Splenic
Common hepatic
24
Q
Splenic artery branches
A
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
