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Biochemistry

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Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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1. What metabolic rxns occur in the mitochondria
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Fibrofatty replacement of muscle - cardiac myopathy
Glucose 6 phosphate dehydrogenase (G6PD)
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

2. What converts NE to epi
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Phenylethamolamine N methyl transferase
75 to 90 - cloverleaf
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway

3. What happens in folate def
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Von hippel lindau - 3
HMG- CoA (HMG- CoA to mevalonate
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs

4. What is the activated carrier for aldehyddes
Comlex II
Hereditary spherocytosis
Anabolic processes as a supply of reducing equivalents
TTP

5. Which phase of the HMP shunt is reversible and Which is irreversible
Purines= A - G pyrimidine = C - T (U)
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Oxidative is irreversible
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22

6. What does GFAP stain for
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Creat a nick in the helix to relieave supercoils created during replication
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Neuralgia

7. Where does gluconeogenesis primarily happen and What are other sites where the enzymes are located
Alkaptonuria - may have debiliating arthralgias
Proline and lysine - vit C
Blood - bone marrown - amniotic fluid - placental tissue
Liver - also in kidney and gut epithelium

8. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
Intermediate filaments
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
AR
Phenylalanine hydroxylase

9. What is linkage disequilibrium
Pyruvate - NAD+ - CoA
Carbomoyl phosphate synthetase I
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

10. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
2 -4 DNP - aspirin
Abnormal protein folding - degradation before reaching cell surface
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
ATP - citrate

11. What is the complication of cystinuria
Blood - bone marrown - amniotic fluid - placental tissue
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
5' to 3'

12. Where are cytosolic and organellar proteins made
Deamination
Cytosol
Free ribosomes
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

13. What clotting factors require vit K
Ribos first then deoxyribos with ribonucleotide reductase
Mediates extra remnant take up
II - VII - IX - X (1972) protein C and S
Protein kinase A

14. An inability to convert orotic acid to UMP would be caused by a deficiency either of which two enzymes

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15. What is the wernicke - korsakoff clinical picture
CAG
Phosphofructokinase 1
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
CarTWOlage

16. What are the characteristics of prader willi syndrome How does it occur
Inc melt - dec fluidity
B6
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Arg - lys - his - arg is most basic - has has no charge at body pH

17. What apolipoprotein is on LDL
B100 and E
VMA
B100
MEN - 2A and 2B with ret gene

18. What does Ehlers Danlos cause and why
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Comlex II
Cytosol
Wrinkles and acne

19. What produces NADPH
HMP shunt
O- oligosaccharaides
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
High output cardiac failure - dilated cardiomyopathy - edema

20. What does aminoacyl tRNA synthetase do the AA before and after it binds to tRNA - and what happens if it's the wrong the match
Scrutinizes - hydrolyzes the bond
O- oligosaccharaides
Proline and glycine (non glycosylated forms)
Terminal regions - tropocollagen

21. What are the two transgenic strategies in mice
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Active secretion in lungs and GI - reabsorbs in skin
Mental retardation - flat facies - prominent epicanthal folds - simian crease - gap between 1st 2 toes - duodenal atresia - congenital heart disease (ASD) - inc risk of All and Alzheimers
TRNA

22. Which end of the tRNA is the amino acid bound to...

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23. What happens in vit D def
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
RER
Connective tissue
TTP

24. Type II collagen
Cartilage - hyaline - vitreous body - nucleus pulposus
Antioxidant - protects RBCs and membrances from free radical damage
Tuberous sclerosis
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

25. What does the golgi assemble proteoglycans from
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Core proteins
Arg - lys - his - arg is most basic - has has no charge at body pH
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

26. What substances inhibit phosphofructokinase -1
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
ATP - citrate
Vit K antagonist
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

27. How does OTC def present
ATP
Evident in first few days of life - can present last onest - excess carbamoyl phosphate converted to orotic acid - orotic acid in blood and urine - dec BUN and symptoms of hyerpammonemia
Malapsorption syndromes like sprue or CF or mineral oil intake
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

28. What does a mischarge tRNA do
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Reads usual codon but inserts wrong AA

29. Type I bone
BOne
Initiate chains
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Ca/calmodulin in muscle to coordinate with muscle activity

30. What is the origin of replication
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Scrutinizes - hydrolyzes the bond
Particular sequence of DNA where replicatino begins - may be single of multiple
P2 +2pq+ = 1

31. Name 5 drugs that interfere with nucleotide synthesis
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
NADH - NADPH - FADH2

32. What is the RDE of glycogen synthesis
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Glycogen synthase
CarTWOlage
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway

33. What is NAD+ generally used for
Dec DNA - dec lymphos leads to SCID
Sucrose = glucose + fructose - lactose = glucose + galactose
9+2 arrangement of microtubules
Catabolic processes to carry reducing equivalents away as NADH

34. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Adds 2 carbon with the help of biotin
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Promotor - TATA box - and CAAT box - AT rich

35. What are the findings in PKU
Phenylalanine hydroxylase
SNP
Fasting
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

36. What is NADPH's role inside RBCs
Hypoglycemia
Neurofibromatosis type 1 (von Recklinghausens disease)
Keep glutathione reduced so it can detoxify free radicals and peroxides
By inhibiting formation of the initiation complex and cause misreading of mRNA

37. What fxn does glucokinase serve in the liver
Marfans
Acetoacetate and beta hydroxybutyrate
Adenosine to inosine
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

38. What converts limit dextran to glucose
Cyclin dependent kinases;constitutive and inactive
Debranching enzyme
Basement membrane or basal lamina
Pyruvate to oxaloacetate (3C to 4C)

39. In eukaryotes - What does RNA poly I make
RRNA
Adds 2 carbon with the help of biotin
Histidine
Result from phagocytic removal of heinz bodies my macs - G6PD def

40. What are the complications/signs of familial hypercholesterolemia
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
THFs
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

41. Where is glucokinase found - What are the Km and Vmax - and what induces it
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Adenosine to inosine
DsRNA promotes degradation of target mRNA knocking down gene expression

42. What enzymes metabolize fatty acids and amino acids
Schwann cells - lens - retina - kidneys
Acetoacetate and beta hydroxybutyrate
Inc vit B6
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR

43. Describe robertsonian translocation
Disorder of aromatic amino acid metabolism
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Deamination
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20

44. What initiates protein synthesis
5' of the incoming nucleotide
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Peroxide

45. What does vit E def cause
Purines= A - G pyrimidine = C - T (U)
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Targets the proteins for lysosome

46. What is the exception to genetic redundancy
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Methionine encode by only 1 codon (AUG)
Night blindness - dry skin
Activates LCAT

47. What bone disorder has x linked dominant inheritance
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Stop codon is recognized by release factor - and completed protein is released from ribosome
APC on chromosome 5

48. What is the TX for PKU
One
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes

49. 1 g of protein or cabrohydrate = ?kcal
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Four

50. What do B- complex vitamin deficiencies often result in
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Specific glycosylases - AP endonuclease
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Dermatitis - glossitis - and diarrhea