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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 is the complication of cystinuria
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Carnitine shuttle - acyl - coa from cyto to mito
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond

2. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
Met - val - arg his
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Intermediate filaments
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

3. What is the energy source after day 3 of starvation
Degredation of TG circulating in chylomicrons and VLDLs
Adipse tissue stores - keton bodies become the main source of energy fo the brain and heart - after these are depleted - vital protein degradation accelerates - leading to organ failure and death
B100 and E
HMG- CoA reductase

4. RNA poly can't proofread - but What can it do
5' of the incoming nucleotide
B100 and E
Initiate chains
Arg and his inc in histones Which bind negatively charged DNA

5. What does PURe As Gold and CUT The Py stand for
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Purines= A - G pyrimidine = C - T (U)
Inc CPK and muscle biopsy
PFK - rate limiting enzyme

6. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Inc vit B6
DNA
Adipse tissue stores - keton bodies become the main source of energy fo the brain and heart - after these are depleted - vital protein degradation accelerates - leading to organ failure and death

7. Where is acetaldehyde located
Leu - lys
TRNA
Mitochondria
The triphosphate bond

8. What does acetyl - CoA become before becoming palmitate
Accelearted muscle breakdown
No
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Silencers

9. In eukaryotes - What does RNA poly II make
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Glycogen synthase
MRNA
Stored ATP - creatine phosphate - anaerobic glycolysis

10. What is the order of severity for the different types of mutations
Base + ribose + phosphate (3' -5') phosphodiester bond
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Nonsense > missense > silent

11. What converts limit dextran to glucose
Debranching enzyme
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Medial dorsal nucleus of thalamus - mamillary bodies
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible

12. How does warfarin work
Cartilage - hyaline - vitreous body - nucleus pulposus
Phosphorylation - glycosylation - hydroxylation
Binds to LDL receptor - mediates VLDL secretion
Vit K antagonist

13. What are the findings in PKU
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Williams syndrome
UDP glucose pyrophosphorylase
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

14. What are purines made from
IMP precursor
Tryosine hydroxylase
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Removes phosphate group from substrate

15. What is variable expression and What is an example
Huntingtons
CGG
B-100 - CII and E
Nature and severity of phenotype vary from 1 individual to another - NF type 1

16. What causes B12 def
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Particular sequence of DNA where replicatino begins - may be single of multiple
UDP glucose pyrophosphorylase
Lariat shape in order and remove intron precisely and join 2 exons

17. What does DNA ligase do
Diphyllobothrium latum
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
1 -25 OH2 D3 = calcitriol
Seals.

18. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Actin and myosin
Initiate chains
Marfans

19. What happens with wet beriberi
High output cardiac failure - dilated cardiomyopathy - edema
X- linked recessive
Same AA - often base change in 3rd position of codon (tRNA wobble)
Schwann cells - lens - retina - kidneys

20. What components come together to make S- adenosyl methionine
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Malabsorption and steatorrhea (ADEK)
ATP and methionine
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive

21. What is the Hardy Weinberg disease prevalence equation
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
P2 +2pq+ = 1
CTG
Core proteins

22. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Autosomal recessive diseases
Alpha - ketoglutarate dehydrogenase complex
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

23. How do stable (quiescent) cells grow and regenerate and What are examples
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
LCAT (lecithin cholesterol acyltransferase)
One
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects

24. What makes up a nucleotide

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25. Where is vit B12 found
Glutamate
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Enhancers

26. What does CATCH 22 stand for and What causes is...
Mcardle's - skeletal muscle glycogen posphorylase
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
HDL

27. What converts DOPA to dopamine
B48 - AIV - CII - E
Dopa decarboxylase
Transfers methyl units
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

28. What apolipoprotiens are on VLDL
B-100 - CII and E
X- linked recessive
Abnormal protein folding - degradation before reaching cell surface
Microarrays

29. In which direction is protein synthesized
N to C
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year
Night blindness - dry skin
Core proteins

30. What test is used for B12 def
Oxidized hemoglobin precipiated within RBCs
Schilling test
NADH - NADPH - FADH2
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin

31. What do def in in enzymes of gluconeogenesis cause
Oligomycin
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Hypoglycemia
Inc intestinal absorption fo calcium and phosphate - inc bone resorption

32. What is the RDE of gluconeogenesis
Facial flushing
Fructose 1 -6 bisphosphate
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Skin

33. Type IV collagen
Inc Cl - in sweat
Basement membrane or basal lamina
NF2 on chromosome 22
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

34. What is uniparental disomy
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Malabsorption and steatorrhea (ADEK)
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Epithelial cells

35. What is the RDE of fatty acid synthesis
Liver - ovaries - seminal vesicles
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Acetyl - CoA carboxylase (ACC)

36. In what cell is collagen synthesis initiated
Fibroblast
Core proteins
Bruton's agammaglobulinemia - wiskott - aldrich - fabrys disease - G6PD def - ocular albinism - Lesch - Nyhan syndrome - Duchenne and Becker Muscular Dystrophy - hunter's syndrome - hemophilia A and B
Facial flushing

37. What does a carboxylase do
Adds 2 carbon with the help of biotin
Disease
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Neural tube

38. What clotting factors require vit K
II - VII - IX - X (1972) protein C and S
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Base + ribose
Neg to pos

39. What do the single stranded binding proteins do
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Comlex II
Prevent strands from reannealing
Autosomal recessive diseases

40. How does patients present with ADPKD
Glycogen and FFA oxidation; glucose conserved for final sprinting
Flank pain - hematuria - HTN - progressive renal failure
Alanine
Fasting

41. What is the fxn of vit D
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Myeloperoxidase
Lysine and leucine
Accelearted muscle breakdown

42. What does biotin def cause
1 -25 OH2 D3 = calcitriol
HMG- CoA (HMG- CoA to mevalonate
Particular sequence of DNA where replicatino begins - may be single of multiple
Dermatitis - alopecia - enteritis

43. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
NADPH
Thymic - parathyroid and cardiac
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

44. What happens at the smooth ER
Liver and leafy veggies
Site of steroid synthesis and detoxification of drugs and poisons
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
G6PD

45. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
Heterochromatin = HighlyCondensed
HDL
Von hippel lindau - 3
Marfans

46. Describe the structure of cilia
Alpha1 antitrypsin
Wrinkles and acne
9+2 arrangement of microtubules
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

47. What is the RDE of de novo pyrimidine synthesis
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
P+q = 1
Carbomoyl phosphate synthetase II
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

48. What is heteroplasmy
Alpha and beta tubulin - dimers have two GTP bound
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Phenytoin - MTX - and sulfonamides
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond

49. What enzyme turns ROS to H2O2
Degradation of TG remaining in IDL
B100 and E
Superoxide dismutase
Result from phagocytic removal of heinz bodies my macs - G6PD def

50. What are the two possible causes of albinism
More than 1 codon may code for the same amino acid
Liver - also in kidney and gut epithelium
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells