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Biochem Flashcards

1
Q

Euchromatin vs heterochromatin

A

Euchromatin- transcribed (“truly transcribed”)

heterochromatin- condensed, transcriptionally active

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2
Q

What amino acids are histones rich in?

A

lysine and arginine- pos charged

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3
Q

What histone is not part of the nucleosome

A

H1

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4
Q

Histone methylation vs acetylation

A

Methylation- represses DAN transcription (“Mute”)

Acetylation- relaxes coiling, allowing for transcription (“Active”)

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5
Q

What are purines vs pyrimidnes?

A

Purines: A, G (2 rings)
Pyrimidines: C, T, U (1 ring)

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6
Q

What amino acids are necessary for purine synthesis?

A

GAG
Glycine
Aspartate
Glutamine

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7
Q

Which pathway is orotic acid involved in?

A

Pyrimidine base production

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8
Q

What pathways are carbamoyl phosphate involved in?

A

de novo pyrimidine synthesis

urea cycle

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9
Q

What does Leflunomide inhibit

A

dihydroorotate reductase (mitochondrial, pyrimidine)

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10
Q

What does mecophenolate inhibit?

A

IMP dehydrogenase (Purine-GMP prod)

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11
Q

What does ribavirin inhibit?

A

IMP dehdrogenase (purine-GMP prod)

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12
Q

What does hydroxyurea inhibit?

A

ribonucleotide reductase (UDP to dUDP)

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13
Q

What do 6-MP and azathioprine inhibit?

A

de novo purine synthesis

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14
Q

Adenoside deaminase deficiency

A

SCID

excess ATP and dATP

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15
Q

Hyperuricemia, gout, self-mutilation

A

Lesch-Nyhan

HGPRT (hypoxanthine to IMP, guanine to GMP)

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16
Q

Describe purine salvage?

A

GMP-Gunanine-Xanthine-Uric acid

AMP-IMP-Hypoxanthine-Xanthine-Uric acid

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17
Q

DNA pol I vs DNA pol III

A

DNA pol III- elongates leading and lagging strand (5’-3’ synth), proofreads with 3’-5’ exonuclease
DNA pol I- degrades RNA primer, replaces with DNA

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18
Q

What is a transition and transversion mutation?

A

Transition- purine to purine or pyrimidine to pyrimidine

Transversion- purine to pyrimidine etc

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19
Q

What is mutated in ataxia tenagiectasia?

A

repair of double stranded breaks

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20
Q

When is nucleotide excision repair vs base excision repair used?

A

nucleotide excision repair- bulky distortion (eg pyrimidine dimer)- done by specific endonucleases
base excision repair- altered base (eg deamination)

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21
Q

What enzymes are involved in base excision repair

A 
Glycosylase removes base
AP-endonuclease cleaves 5' end
Lyase cleaves 3' end
DNA polymerase b fins gape
ligase seals
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22
Q

How are DNA, RNA and protein synthesized?

A

DNA, RNA: 5’-3’

Protein- N to C terminus

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23
Q

What do the RNA polymerases do?

A

RNA pol I: makes rRNA
RNA pol II: makes mRNA (opens DNA at promoter site
RNA pol III: makes tRNA

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24
Q

a-amanitin toxicity

A

inhibits RNA pol II

severe hepatotoxicity

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25
Q

How is RNA processed? where is this done?

A

5’ capped with methylguanosine
3’ polyadenylation
splicing out of introns
in nucleus

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26
Q

How are pre-mRNAs processed

A

snRNPs form lariat intermediate

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27
Q

What do the T-arm, D-arm, and stem of tRNAs do?

A

T-arm: binds to ribosome (thymine, pseudouridine, cytosine residue)
D-arm: allows for recognition of correct tRNA by aminoacyl tRNA synthetase
stem: 3’ CCA accepts amino acid

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28
Q

What are Nissl bodies?

A

RER in neurons

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29
Q

What modifications can RER make?

A

N-linked oligosaccharide to protein

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30
Q

What modifications can Golgi make?

A

N-oligosaccharide on asparagine

O-oligosaccharide on serine, threonine

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31
Q

What is the signal for trafficking to the lysosome?

A

mannose-6-phosphate

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32
Q

Course facial features, clouded corneas, restricted joint movement, high plasma levels lysosomal enzymes

A

I-cell disease
deficiency phosphotransferase
cant phosphorylate mannose residue- secreted extracellulary instead of to lysosome

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33
Q

What do the vesicular trafficking proteins indicate (COPI, COPII, clathrin)

A

COPI- retrograde golgi, Golgi to ER
COPII- anterograde golgi, ER to golgi
Clathrin- trans-golgi to lysosome; plasma membrane- endosome

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34
Q

What disease has proteasome defect been implicated in?

A

Parkinsons

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35
Q

Dynein vs kinesin

A

Dynein- retrograde (+ to -)

kinesin- anterograde

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36
Q

What is axonemal dynein do?

A

ATPase powers cilia bending

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37
Q

What is the molecular mechanism of digoxin?

A

inhibits NaKATPase

indirect inhibition of Na/Ca2+ exchainge, incr Ca2+, incr contractility

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38
Q

What is the most abundant protein in the human body

A

collagen

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39
Q

What do the different types of collagen do?

A

I: bone, skin, tendon, dentin, fascia, cornea, wound repair
II: cartilage, vitreous body, nucleus puplosus
III: skin, blood vessels, uterus, fetal tissue, granulation tissue
IV: basement membrane, basal lamina, lens

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40
Q

What types of collagen are mutated in Ehlers-Danlos?

A 
Classic type (joint + skin)- mutation in type V collagen
Vascular type (vascular, organ rupture)- deficiency in type III collagen
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41
Q

Brittle, kinky hair, growth retardation, hypotonia

A

Menkes disease
impaired copper absorption
decr activity lysyl oxidase

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42
Q

What is the most abundant amino acid in collagen

A

glycine

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43
Q

What modifications are made to collagen?

A 
Inside fibroblast:
hydroxylation of proline and lysine
glycosylation of hydroxylysine
Outside fibroblast: 
cleavage of disulfide-rich terminal regions and crosslinking (lysyl oxidase)
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44
Q

What amino acids make up elastin?

A

proline and glycine

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45
Q

What genetic disease typically shows mosaicism

A

mccune albright

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46
Q

Hyperphagia, obesity, intellectual disability, hypogonadism, hypotonia

A

Prader-Willi

Paternal gene is deleted or mutated (25% from maternal uniparental disomy) Chr 15

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47
Q

Inappropriate laughter, seizures, ataxia, severe intellectual disability

A

Angelman syndrome

Maternal gene is deleted or mutated (5% from paternal uniparental disomy) Chr 15

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48
Q

myopathy, lactic acidosis, CNS

ragged red fibers on muscle biopsy

A

mitochondrial myopathies

failure of ox phs

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49
Q

Vitamin-D resistant rickets

name and inheritance

A

Hypophosphatemic rickets

incr phosphate wasting in proximal tubule

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50
Q

Telangiectasia, recurrent epistaxis, skin discoloration, AVM, GI bleed, hematuria

A

Hereditary hemorrhagic telangiectasia

autosomal dominant

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51
Q

Inheritance of MEN

A

Aut dom

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52
Q

Colon covered with adenomatous polyps before puberty

A

Familial adenomatous polyposis
APC gene Ch 5
Aut DOm

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53
Q

cafe-au-lait spots and cutaneous neurofibromas

A

NF-1
Chr 17
Aut Dom- 100% penetrance, variable expressivity

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54
Q

bilateral acoustin schwannomas, juvenile cataracts, meningiomas, ependymomas

A

NF2
Chr 22
Aut Dom

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55
Q

Numerous benign hamartomas, multiple organ involvement

A

tuberous sclerosis

Aut Dom- incomplete penetrance, variable expressivity

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56
Q

What is the treatment for CF?

A 
N-acetylcystein to loosen mucous plug
Dornase alta (DNAse) to clear leukocytic debris
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57
Q

How is CF diagnosed?

A

Cl- in sweat >60mEq/L

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58
Q

Describe the physiology of CF?

A

Defect in ATP-gated Cl- channel
Cant secrete Cl- in lungs and gut and sweat
Incr intracellular Cl-
Incr compensatory excretion Na+ absorption and H20 absorption
thick mucus

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59
Q

Myotonia, muscle wasting, frontal balding, cataracts, testicular atrophy, arrythmia

A

Myotonic type 1 muscular dystrophy
CTG trinucleotide repeat of DMPK gene
Abnormal expression of myotonin protein kinase

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60
Q

Post-pubertal macroorchidism, long face with large jaw, large everted ears, autism, mitral valve prolapse

A

Fragile X
methylation and expression FMR1 gene
Trinucleotide repeat: CGC

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61
Q 
What trinucleotide repeats cause
Fragile X
Friedreich ataxia
Huntington
Myotonic dystrophy
A

Fragile X- CGG
Friedreich- GAA
Hungtington-CAG
Myotonic dystroph- CTG

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62
Q

Severe intellectual disability, rocker-bottom feet, micrognathia, low-set ears, clenched hands, prominent occiput

A

Edwards, Trisomy 18

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63
Q

Severe intellectual disability, rocker-bottom feet, microphtalmia, microcephaly, cleft lip/palate, holoprosencephaly, polydactyly

A

Patau syndrome, trisomy 13

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64
Q

microcephaly, intellectual disability, high pitched crying, epicanthal folds, VSD

A

Cri-du-chat

microdeletion of short arm of chromosome 5

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65
Q

defect in DiGeorge or velocardiofacial

A

22q11 deletion

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66
Q

What vitamins are stored in the liver?

A

B12, folate

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67
Q

Often cause dermatitis, glossitis, diarrhea

A

Vit B deficiencies

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68
Q

Fat sol vitamins

A

ADEK

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69
Q

Another name for B1

A

thiamine, TPP

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70
Q

Another name for B2

A

riboflavin: FAD, FMN

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71
Q

Another name for B3

A

Niacin

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72
Q

Another name for B5

A

pantothenic acid: CoA

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73
Q

Another name for B6

A

pyridoxine: PLP

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74
Q

Another name for B7

A

biotin

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75
Q

Another name for B9

A

Folate

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76
Q

Another name for B12

A

Cobalamin

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77
Q

Night blindness, dry, scaly skin, alopecia, corneal degeneration, immune suppression

A

Vit A

prevents squamous metaplasia, component of retinal

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78
Q

How is diagnosis of thiamine deficiency made?

A

incr RBC transketolase activity after Vit B1 administration

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79
Q

Confusion, ophtalmoplegia, ataxia, confabulation, memory loss

A

Wernicke Korsakoof syndrome

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80
Q

Dry vs wet beriberi

A

Dry: polyneuritis, symmetrical muscle wasting
Wet: high output cardiac failure (dilated cardiomyopathy), edema

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81
Q

Cheilosis, corneal vascularization

A

Vit B2 deficiency (riboflavin)

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82
Q

Glossitis, diarrhea, dermatitis, dementia

A

Vit B3 (niacin) deficiency

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83
Q

What enzymes use thiamine? (4)

A

pyruvate dehydrogenase (links glyoclysis, TCA)
a-ketoglutarate dehydrogenace (TCA)
Transketolase (HMP shunt)
Branched-chain ketoacid dehydrogenase

84
Q

Dermatitis, eneteritis, alopecia, adrenal insufficiency

A

Vit B5 (pantothenate) deficeincy

85
Q

Convulsions, hyperiritability, peripheral neuropathy, sideroblastic anemia

A

Vit B6 (pyridoxine) deficiency

86
Q

What reactions require pyridoxine? (3)

A

PLP- transamination, decarboxylation reactions, glycogen phosphorylase

87
Q

What is vitamine B7 a coenzyme for?

A

carboxylation enzymes (eg pyrovate carboxylase, acetylCoA carboxylase, propionyl CoA carboxylase)

88
Q

Macrocytic, megaloblastic anemia, hypersegmented PMNs, incr homocystein, normal methylmalonic CoA

A

Folic acid (B9) deficiency

89
Q

Macrocytic, megaloblastic anemia,

paresthesias, subacute combined degeneration, hypersegmented PMNs, incr homocystein, incr methylmalonic CoA

A

B12 (cobalamin) deficiency

90
Q

What important synthetic reactions is VitC involved in?

A

hydroxylation of proline and lysine- collagen synthesis

dopamine b-hydroxylase- converts dopamine to NE

91
Q

Where is excess vitamin D likely?

A

sarcoidosis (incr activation of vit D by epithelioid macrophages)

92
Q

Hemolytic anemia, acanthocytosis, muscle weakness, posterior column and spinocerebellar tract demyelination

A

Vit E deficiency

93
Q

What reaction is vit K important for?

A

g-carboxylation of glutamic acid

94
Q

Delayed wound healing, hypogonadism, decr adult hair, dysguesia, anosmia, acrodermatitis enteropathica

A

Zinc deficiency

95
Q

What are the metabolic consequences of excess ethanol in the liver?

A

Incr NADH/NAD+ ratio
lactic acidosis
prevents gluconeogenesis- hypoglycemia (oxaloacetate-malate)
hepatosteatosis

96
Q

Kwashiorkor vs Marasmus

A

Kwashiorkor- skin lesions, edema, liver malfunction (swollen belly- decr apolipoprotein synth)
Marasmus- tissue and muscle wasting, loss of subcut fat, variable edema

97
Q

What 3 pathways take place in both the mitochondria and cytoplasm?

A

HUGs take two:
Heme synthesis
Urea cycle
Gluconeogenesis

98
Q

What is the rate-determining step of glycolysis? What regulates it? (4)

A

Phosphofructokinase-1 (PFK-1)
AMP+, fructose-2,6-bisphospate+
ATP-, citrate-

99
Q

What is the rate-determining step of gluconeogenesis? What regulates it? (4)

A

Fructose-1,6-bisphosphatase
ATP+, AcetylCoa+
AMP- fructose 2,6 bisphosphate-

100
Q

What is the rate-determining step of the TCA cycle? What regulates it? (3)

A

Isocitrate dehydrogenase
ADP+
ATP-, NADH-

101
Q

What is the rate-determining step of glycogenesis? What regulates it? (5)

A

Glycogen synthase
G6P+, insulin+, cortisol+
Epinephrine-, glucagon-

102
Q

What is the rate-determining step of glycogenolysis? What regulates it? (6)

A

Glycogen phosphorylase
Epinephrine+, Glucagon+, AMP+
G6P-, insulin-, cortisol-

103
Q

What is the rate-determining step of de novo pyrimidine synthesis?

A

Carbamoyl phosphate synthetase II

104
Q

What is the rate-determining step of de novo purine synthesis?

A

Glutamine-PRPP amidotransferase

105
Q

What is the rate-determining step of the urea cycle? What regulates it? (1)

A

Carbamoyl phosphate synthetase I

N-acetylgultamate+

106
Q

What is the rate-determining step of fatty acid synthesis? What regulates it? (4)

A

Acetyl-CoA carboxylase (ACC)
insulin+, citrate+
glucagon-, palmitoyl-CoA-

107
Q

What is the rate-determining step of fatty acid oxidation? What regulates it? (1)

A

carnitine acyltransferase I

Malonyl-Coa-

108
Q

What is the rate-determining step of ketogenesis?

A

HMG-CoA synthase

109
Q

What do hexokinase and glucokinase do?

A

Both convert glucose to glucose 6-P
Hexokinase- most tissues; sequesters glucose in tissues at low concentrations (low Km, Vmax(
glucokinase- liver only, under control of liver, no neg feedback by G6P; stores glucose in liver at high concentrations (high Km, Vmax)

110
Q

Describe the use of NAD vs NADP

A

NAD+- used in catabolic processes

NADPH- used in anabolic processes (product of HMP shunt)

111
Q

How is the amount of Fructose-2,6-bisphosphate regulated?

A

F26BP- favors glycolysis
FBPase-2 (promotes F6P) and PFK-2 (promotes F26BP) regulate
Fasting state- incr glucagon- PKA activtiy- incr FBPase2, decr PFK2– gluconeogenesis
fed state- incr insluin- decr PKA activity- decr FBPase2, incr PFK2— glycolysis

112
Q

Vomiting, rice-water stools, garlic breath

A

arsenic poisoning

inhibition of lipoic acid

113
Q

What does pyruvate dehydrogenase complex do?

A

links glycolysis and TCA cycle

pyruvate, NAD+, CoA– acetylCoa, CO2, NADH

114
Q

What cofactors does pyruvate dehydrogenase complex require?

A

B1, B2, B3, B5, Lipoic acid

115
Q

Neurologic defects, lactic acidosis, incr serum alanine

A

Pyruvate dehydrogenase complex deficiency

Treat with ketogenic nutrients (high fat, lysine, leucine)

116
Q

What are the only purely ketogenic amino acids?

A

Lysine, leucine

117
Q

What are the 4 possible metabolites of pyruvate?

A

Alanine (ALT, B6)
Oxaloacetate (pyruvate carboxylase, biotin)
AcetylCoA (pyruvate dehydrogenase)
Lactate (lactate dehydrogenase- b3)

118
Q

Retonone

A

Inhibits Complex I

electron transport inhibitor

119
Q

Cyanide

A

inhibits complex IV

electron transport inhibitor

120
Q

Oligomycin

A

Inhibits complex V

ATP synthase inhibitor

121
Q

2,4 dinitrophenol

A

uncoupling agent

illicit weight loss agent

122
Q

What tissues can participate in gluconeogenesis? What enzyme is essential?

A

Mostly liver
also kidney, epithelium
muscle cant: no glucose-6-phosphate

123
Q

Pyruvate decarboxylase

Where does it take place? what required?

A

gluconeogenesis
in mitochndria: pyruvate to oxaloacetate
Requires biotin, ATP; activated by acetylCoA

124
Q

What fatty acids can contribute to gluconeogenesis?

A

only odd chain fatty acids (via succinyl CoA)

125
Q

Phosphoenolpyruvate carboxykinase

How is it regulated? What does it do? Where?

A

oxaolacetate to PEP
in cytosol
requires GTP
regulated transcriptionally by glucagon, cortisol

126
Q

What does glucose-6 phosphatase do? where?

A

Glucose-6-P to glucose
in ER of liver
deficient in von-geirke

127
Q

What does the HMP shunt do?

A

Yields NADPH from Glucose-6-P, also ribose for nucleotide synthesis

128
Q

What is the rate limiting stelp of HMP shunt

A

Glucose-6-P dehydrogenase

oxidative, irreversible

129
Q

What is an important conezyme for HMP shunt pathway?

A

B1

nonoxidative, make G3P, F6P

130
Q

What is the advantage of G6PD def?

A

incr malarial resistance

131
Q

Fructose in blood and urine; relatively asymptomatic

A

essential fructosuria
defect in fructokinase (Fructose to Fructose-1-P)
Aut Rec

132
Q

Hypoglycemia, faundice, cirrhosis, vomiting

reducing sugars in urine

A

Fructose intolerance
deficiency in aldolase B
Fructos1P to dihdryacteoneP, glcyeraldehyde
Decrease in phosphate- inhibition of glycogenolysis, gluconeogenesis

133
Q

Infantile cataracts

galactose in blood and urine

A

galactokinase deficiency
Aut R
accumulation of galacticol

134
Q

failure to thrive, jaundice, hepatomegaly, infantile cataracts, intellectual disability

A

classic galactosemia
defect in galactose-1-phosphate uridyltransferase
Aut R
accumulation galacticol, phosphate depletion

135
Q

What cell types have aldose reductase and sorbitol dehydrogenase?
What cell types have only aldose reductase?

A

both: liver, ovaries, seminal vesicles
AR only: schann cells, retina, kidneys, lens
At risk for osmotic damage due to accum of sorbitol

136
Q

Bloating, cramps, flatulence, osmotic diarrhea

decr pH stool, incr hydrogen content breath

A

lactase deficiency

137
Q

What are the glucogenic aminoacids?

A

Methionine, valine, histidine

138
Q

What are the acidic aminoacids? Charge at body pH?

A

aspartic acid, glutamic acid

negatively charged

139
Q

What are the basic amino acids? What is the charge at body pH?

A

Arginine, lysine, histidine
Important part of histones
His has no charge

140
Q

What do alterations in BUN levels indicate?

A

incr BUN- kidney dysfunction

decr BUN- liver dysfunction

141
Q

What is an obligate cofactor of the urea cycle?

A

N-acetylgultamate

Req for carbamoyl phosphate synthesis

142
Q

What reactions of the urea cycle take place in the mitochondria?

A

Carbamoyl phosphate synthetase I

Ornithine transcarbamylase

143
Q

Tremor, slurring of speech somonlence, vomiting, cerebral edema, blurring of vision

A

Ammonia intoxicification

144
Q

How is hyperammonia treated?

A

Benzoate or phenybutyrate (bind AA- secretion)

Lactulose- GI trap

145
Q

Describe pathogenesis of hyperammonemia?

A

depletion of a-ketoglutarate (via NH4 excess)

inhibition of TCA cycle

146
Q

What are the advantages/ disadvantages of alanine vs cori cycle? What do they both do?

A

Cori- regenerates NAD+
also causes acidosis
transports alananine and glutamate to liver

147
Q

How is N-acetylglutamate deficiency distinguished from carbamoyl phosphate synthetase-1 deficiency?

A

both hyperammonemia

N-acetylglutamate: incr ornithine with normal urea cycle enzymes

148
Q

Hyperammonemia, incr orotic acid in blood in urine, decr BUN

A

Ornithine transcarbamylase deficiency
Excess carbamoly phosphate converted to orotic acid
X-lined recessive
no megaloblastic anemia

149
Q

What amino acid is melatonin derived from? What factors required?

A

Tryptophan

BH4, B6

150
Q

What amino acid is niacin derived from?

A

trypotphan

151
Q

What amino acids is serotonin derived from?

A

tryptophan

152
Q

What amino acid are catecholamines derived from?

A

phenylalanine/tyrosine

153
Q

What is GABA derived from?

A

glutamate

154
Q

What is heme derived from?

A

glycine

155
Q

What is histamine derived from?

A

histidine

156
Q

Intellectual disability, growth retardation, seizures, fair skin, eczema, musty odor

A

phenylketonuria

157
Q

What enzymes are derfective in PKU? What amino acid is now essential?

A

phenlyalanine hydroxylase
tetrahydrobiopterin cofactor
tyrosine essential

158
Q

Dark connective tissue, brown pigmented sclerae, urine turns black when exposed to air, arthralgia

A

alkaptonuria
homogenistic oxidase deficiency
aut rec
involved in degredation of tyrosine to fumarate

159
Q

incr homocysteine in urine, intellectual disability, osteoporosis, tall stature, kyphosis, lens subluxation, thrmobosis, atherosclerosis

A

homocystinuria

160
Q

What enzymes can be defective in homocystinuria? What is treatment for each?

A

cystathionine deficiency- decr methionine, incr cysteine, incr B12 and folate in diet
Decr affinity of cystahione synthase for PLP: incr B6, incr cysteine
homocysteine methyltransferase deficiency: treat by incr methionine

161
Q

Cyanide nitroprusside test is positive

A

cystinuria

162
Q

Defect in cystinuria

A

hereditary defect of renal PCT and intestinal amino acid transporter
Cysteine, ornithine, lysine, arginine

163
Q

Treatment of cystinuria

A

urine alkalization

chelating agents

164
Q

severe CNS defects, intellectual disability, death, branched chain ketoacids in blood

A

maple syrup urine disease

decr a-ketoacid dehydrogenase

165
Q

Treatment of maple syrup urine disease

A

restriction of leucine, isoleucine, valine in diet

thiamine supplementation

166
Q

How are glycogen phosphorylase and glycogen synthase regulated?

A

Glycogen phosphorylase (makes glucose)
-inhibited by protein phosphatases that activated by insulin
-activated by glycogen phosphorylase kinase that activated by glucagone (via PKA), calcium (epinephrine)
Glycogen synthase
-activated by insulin tyrosine kinase
-inhibited by PKA

167
Q

Describe the bonds in glycogen

A

Branches: a(1-6) bonds
Linkages: a(1-4) bonds

168
Q

Describe the process of glycogen breakdown

A

glycogen phosphorylase removes glucose-1-P
when down to 4 (limit dextrin), 4-a-D-glucanotransferase (debranching enzyme) removes 3
a-1,60glucosidase cleaves of last of branch

169
Q

severe fasting hypoglycemia, incr glycogen in liver, incr blood lactate, hepatomegaly

A 
Von Gierke (type I)
defect in glucose-6-phosphatase
AR
170
Q

cardiomyopathy, muscle weakness, early death

A 
Pompe disease (type II)
defect in lysosomal a-1,4-glucosidase
AR
171
Q

Fasting hypoglycemia, incr glycogen in liver, normal blood lactate, hepatomegaly

A 
Cori disease (Type III)
defect in debranching enzyme (a-1,6-glucosidase)
AR
172
Q

painful muscle cramps, myoglobinuria, arrythmia

A

McArdle disease (Type V)
myophosphorylase (glycogen phosphorylase)
AR

173
Q

Peripheral neuropathy of hands and feet, angiokeratoma, cardiovascular and renal disease

A

Fabry
a-galactosidase-A def
accum ceramide trihexoside
XR

174
Q

Hepatosplenomegaly, pancytopenia, bone crises, aseptic necrosis of bone, crumpled tissue paper macrophages

A

Gaucher
glucocerebrosidase
gucocerbroside accum
AR

175
Q

Progressive neurodegeneration, hepatosplenomegaly, Cherry-red macula spot, foam cells

A

Neimann-Pick
sphingomyelinase
Sphingomelin accum
AR

176
Q

Progressive neurodegeneration, developmental delay, no hepatomegaly, Cherry-red macula spot, lysosomes with onion skin

A

Tay Sachs
hexosaminidase A
GM2 ganglioside accum
AR

177
Q

Peripheral neuropathy, developmental delay, optic atrophy, globoid cells

A

Krabbe disease
Galactocerbrocidase
Galactrocerebroside and psychosine accum
AR

178
Q

Central and peripheral deymelination

ataxia, dementia

A

Metacrhomatic leukodystrophy
arylsulfatase A
cerebroside sulfate
AR

179
Q

Developmental delay, gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly

A

Hurler syndrome
a-L-iduronidase
heparan sulfate, dermatan sulfate
AR

180
Q

Developmental delay, gargoylism, airway obstruction, hepatosplenomegaly, aggressive behavior

A

Hunter syndrome
iduronate sulfatase
heparan sulfate, dermatan sulfate
XR

181
Q

Weakness, hypotonia, hypoketotic hypoglycemai

A

carnitine deficiency

inability to transport LCFAs to mitochondria

182
Q

Decr dycarboxylic acids, decr glucose, decr ketones

A

acyl-CoA dehydrogenase deficiency

acetyl-CoA required for pyruvate carboxylase in gluconeogenesis

183
Q

Why do alcoholics have incr production of ketone bodies

A

excess NADH shunts oxaloacetate to malate

184
Q

How many calories in protein, carbohydrate, fat, alcohol?

A

Protein, carbohydrate: 4 cal
Fat: 9 cal
Alcohol: 7 cal

185
Q 
How long does each last?
ATP
Creatine phosphate
anaerobic metabolism
aerobic metabolism
A

ATP: 2 sec
Creat phosphate: 10 sec
Anaerobic metabolism: 1 min
Aerobic: plateaus 1 min

186
Q

How long does it take to deplete glycogen stores?

A

1d

187
Q

What to LPLs do?

A

degrade TG circulating in chylomicrons and VLDLs

found on vascular endothelial surface

188
Q

What to hepatic lipases do?

A

degrade TG in IDL

189
Q

What do hormone-sensitive lipases do?

A

degrad TG in adipocytes

190
Q

What do LCAT and CETP do?

A

LCAT- esterification of cholesterol- helps for mature HDL
CETP- helps transfer cholesterol esters from HDL to other lipoproteins
esterified cholesterol is trapped in lipoprotein, cant diffuse across membrane

191
Q

What does Apolipoprotein E do? Where is it found?

A

mediates remnant uptake

Found on all but LDL

192
Q

What does Apolipoprotein A1 do? Where is it found?

A 
activates LCAT (esterification of cholesterol)
on chylomicron, HDL
193
Q

What does Apolipoprotein C-II do? Where is it found?

A

cofactor for LPL

chylomicron, VLDL, HDL

194
Q

What does Apolipoprotein B-48 do? Where is it found?

A

mediates chylomicron secretion

chylomicron, chylomicron remnant

195
Q

What does Apolipoprotein B-100 do? Where is it found?

A

Binds LDLR

VLDL, IDL, LDL

196
Q

What lipoproteins are highest in cholesterol? What do they do?

A

LDL and HDL
LDL transports chol from liver to tissues
HDL transports chol from tissue to liver

197
Q

What does chylomicron do? what receptors?

A

delivers TGs to peripheral tissue (from intestinal)
delivers cholesterol to liver as chylomicron remant
E,A,C, B48 (all but B100)

198
Q

What does VLDL do? what receptors?

A

delivers hepatic TGs to peripheral tissues (from liver)

E,C,B100

199
Q

What does IDL do? what receptors?

A

degradation of VLDL, delivers TGs and cholesterol to liver

E, B100

200
Q

What does LDL do? what receptors?

A

delivers hepatic cholesterol to peripheral tissue (formed in liver from IDL)
taken up via receptor-mediated endocytosis
B100 only

201
Q

What does HDL do? what receptors?

A

mediates transport of cholesterol from periphery to liver

acts as repository for apoC and apoE

202
Q

What lipoprotein is increase by alcohol?

A

HDL

203
Q

pancreatitis, hepatosplenomegaly, pruritic xanthoams

A

I- hyperchylomicronemia
AR
lipoprotein lipase deficiency or altered lipoprotein C

204
Q

accelerated atherosclerosis, tendon xanthomas, corneal arcus

A

IIa- familial hypercholesterolemia
Codominant/ autosomal dominant
absent or defective LDLR

205
Q

pancreatitis, incr VLDL

A

IV- familial hypertriglycidemia

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