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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 lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
B100
PCR - denaturation - annealing - elongation
Pyruvate - NAD+ - CoA
Breaks down acyl - coa to acetyl coa groups in mito

2. What does the vimentin stain for
Connective tissue
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
LCAT (lecithin cholesterol acyltransferase)

3. What rxn does propionyl - CoA carboxylase catalyze
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
HGPRT - defective purine salvage - excess uric acid production
Palate - facial and cardiac defects
PFK - rate limiting enzyme

4. What happens in termination of proteins synthesis
Stop codon is recognized by release factor - and completed protein is released from ribosome
Colchicine
Sons of heterozygous mothers have 1/2 half chance of being affected - no male to male transmission - and often more severe in males - heterozygous females may be affected
Mediates extra remnant take up

5. What are cyclins
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Proline and glycine (non glycosylated forms)
Nine
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

6. What is the energy source in the fed state right after a meal
Glycolysis and aerobic respiration
UGA - UAA and UAG
Kwashiorkor - small child with swollen belly
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

7. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
HGPRT - defective purine salvage - excess uric acid production
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Reads usual codon but inserts wrong AA

8. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Neither of 2 alleles is dominant - blood groups
Essential fructosuria - fructokinase AR
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

9. What does commaless - nonoverlapping genetic code refer to...
Read from a fixed starting point as a continuous sequence of bases
Oxalacetate
HMG- CoA synthase
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

10. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Tuberous sclerosis
2 -4 DNP - aspirin
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Cre - lox system

11. What does a defective Cl channel do
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
HMG- CoA (HMG- CoA to mevalonate
Night blindness - dry skin

12. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
Q -
32 - malate aspartate shuttle
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Consesus sequenec of base pairs

13. Which anticancer drugs work on microtubules
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
PCR - denaturation - annealing - elongation
Passed to glutamate - then to alanine enters blood - enters liver - coverted to pyruvate and transfers ammonium back to glutamate which gives it to the urea cycle
Vincritsine/vinblastine

14. What is the RDE of the HMP shunt
2 rings
Glucose 6 phosphate dehydrogenase (G6PD)
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome

15. What is the source of energy in the fasting state between meals
Von Gierke's - Pompe - Cori - McArdle
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Cyclin dependent kinases;constitutive and inactive

16. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users

17. What is RNAi used for
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
DsRNA promotes degradation of target mRNA knocking down gene expression
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
PFK - rate limiting enzyme

18. What does Citrate Is Krebs starting substrate for making oxaloacetate
DNA
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

19. What is sorbitol - how and why is it made
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Flank pain - hematuria - HTN - progressive renal failure
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
O- oligosaccharaides

20. What does acetyl - CoA become before becoming palmitate
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
By inhibiting formation of the initiation complex and cause misreading of mRNA
Degradation of TG stored in adipocytes

21. In which direction is protein synthesized
N to C
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Mucus secreting globlet cells and antibody secreting plasma cells
Debranching enzyme

22. What are the findings in Lesch - Nyhan
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Protective against malaria
Scrutinizes - hydrolyzes the bond
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes

23. Why enzyme breaks down elastin and what enzyme inhibits it
Proline and lysine - vit C
Phenylalanine
Elastase - inhibited by alpha1 antitrypsin
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21

24. What does universal genetic code refer to and What are some exception
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Polyneuritis - symmetrical muscle wasting

25. What converts tyrosine to DOPA
Phenytoin - MTX - and sulfonamides
Cofactor for LPL
Glutamate
Tryosine hydroxylase

26. What is the activated carrier for Co2
Disorder of aromatic amino acid metabolism
Biotin
No - its non homologous
Alpha1 antitrypsin

27. How does insulin inhibit glycogenolysis
SAM
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
VLDL
HMG- CoA synthase

28. How do glucagon/epi lead to glycogenolysis
Seals.
Acetly- CoA - CO2 - NADH
Activates LCAT
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

29. How many ATP are created by aerobic metobolism of glucose in muslce via what shuttle
Ile - phe - thr - trp
In ER - glucose 6- P to glucose
Lariat shape in order and remove intron precisely and join 2 exons
30 - glycerol -3- phosphate shuttle

30. What tissues have both enzymes of sorbitol metabolism
Liver - ovaries - seminal vesicles
Acetoacetate and beta hydroxybutyrate
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Malapsorption syndromes like sprue or CF or mineral oil intake

31. What substance inside the cells replenishes NADPH
Paclitaxel
Activates LCAT
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
G6PD

32. What reaction does adenosine deaminase normally catalyze
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Adenosine to inosine
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Proline and lysine - vit C

33. What are the characteristics of prader willi syndrome How does it occur
Nature and severity of phenotype vary from 1 individual to another - NF type 1
X linked frame shif mutation
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
After day 1

34. Mild Hurlurs + aggressive behavior no corneal clouding
After citruline
Procollagen - triple helix of 3 alpha collagen chains
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Kidney - ears - eyes

35. What is the energy source for translocation
Site of steroid synthesis and detoxification of drugs and poisons
EtOH dehydrogenase and acetaldehyde dehydrogenase
SAM
GTP

36. What is the RDE of gluconeogenesis
Fructose 1 -6 bisphosphate
SAM
Adenosine to inosine
Adds 2 carbon with the help of biotin

37. What does inc phenylalanine lead to...
Cleft palate - cardiac abnl - pregs test
Polyneuritis - symmetrical muscle wasting
Phenylketones in urine
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent

38. Why does alpha amanitin cause liver failure and Where is it found
Kidney - ears - eyes
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Fed
Inhibits RNA polymerase II - found in death cap mushrooms

39. Why is albinism inheritnace varialbe due to...
TRNA
Orotic acid to UMP
Familial hypercholesterolemia - hyperlipidemia type IIA
Locus heterogeneity - ocular albinism is x- linked recessive

40. What is the TX for hyper ammonemia
Abnormal protein folding - degradation before reaching cell surface
RRNA
Hypoxanthine to xanthing and xanthine to uric acid
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

41. 90% of ADPKD cases are due to a mutation In what gene
APKD1 on chromosome 16
Antibiotic use or excessive ingestion of raw eggs
Microtubules
Oral uridine administration

42. What initiates protein synthesis
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Same AA - often base change in 3rd position of codon (tRNA wobble)

43. What is the purpose of the HMP shunt
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Connective tissue
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Actin and myosin

44. What else can phosphoylate phosphorylase kinase
Ca/calmodulin in muscle to coordinate with muscle activity
PFK - rate limiting enzyme
Activates LCAT
Peroxide

45. Which antifungal drugs work on microtubules
DsRNA promotes degradation of target mRNA knocking down gene expression
Griseofulvin
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
II - VII - IX - X (1972) protein C and S

46. What is the amino acid precuros for niacin and serotonin/melatonin
Tryptophan
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Foliage - small reserve in liver - eat green leaves
Myeloperoxidase

47. What does primase do
Read from a fixed starting point as a continuous sequence of bases
Makes RNA primer on which DNA poly III can initiate replication
CAG - 4
LCAT (lecithin cholesterol acyltransferase)

48. Type IV BM
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Von hippel lindau - 3
Night blindness - dry skin
4 under the floor

49. What is pleiotropy and given an example
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Hypoxanthine to xanthing and xanthine to uric acid

50. What happens in vit D def
Post to neg
Inhibits 50S peptidyltransferase
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
African Americans and Asians