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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. How do labile celss grow and regenerate and What are examples
IMP precursor
FAP
Binds 50S - blocking translocation
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles

2. Why does alpha amanitin cause liver failure and Where is it found
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Inhibits RNA polymerase II - found in death cap mushrooms
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

3. Giving folate during early pregnancy is important to prevent what birth defects
Medial dorsal nucleus of thalamus - mamillary bodies
EtOH dehydrogenase and acetaldehyde dehydrogenase
Neural tube
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan

4. How many ATP are produced by anearobic glycolysis per molecule of glucose
Two
Neural tube
HMG- CoA synthase
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

5. What is DNA cloning and How do you do it?
Rb and p53
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Acetly- CoA - CO2 - NADH
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

6. 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
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Facial flushing
Tyrosine

7. What is the activated carrier for electrons
5' of the incoming nucleotide
Glutamate
LDL
NADH - NADPH - FADH2

8. characterize autosomal recessive inheritance
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
CAG
30 - 50 - 70

9. When does aspartate enter the urea cycle
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Cofactor for LPL
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
After citruline

10. How do macrolides and clindamycin work
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Binds 50S - blocking translocation
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

11. What does a southern blot use as its sample
Tryosine hydroxylase
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
DNA
Neither of 2 alleles is dominant - blood groups

12. Where is PEP carboxykinase found - What does it do - and What does it require
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Acetly- CoA - CO2 - NADH

13. What does the golgi add to serine and threonine residues
Four
Dec in alpha ketoacid dehydrogenas leading to blocked degredation of branches amino acids like Ile - Leu - and Val - severe CNS defects mental retardation and death
Achondroplasia
O- oligosaccharaides

14. What is the active form of vit D
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
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
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
1 -25 OH2 D3 = calcitriol

15. What is anticipation and give an example
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Carbomoyl phosphate synthetase II
Adenosine to inosine

16. Why is albinism inheritnace varialbe due to...
Metanephrine
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Locus heterogeneity - ocular albinism is x- linked recessive
Dermatitis - alopecia - enteritis

17. RNA poly can't proofread - but What can it do
Initiate chains
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Result from phagocytic removal of heinz bodies my macs - G6PD def
Cleft palate - cardiac abnl - pregs test

18. What is the limiting reagent in EtOH metabolism
Defect in fibrillin
NAD+
Phenylalanine hydroxylase
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

19. What are cyclins
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Lariat shape in order and remove intron precisely and join 2 exons
Carnitine shuttle - acyl - coa from cyto to mito

20. What is the main source of folate
Foliage - small reserve in liver - eat green leaves
Glycogen phosphorylase
Abnormal protein folding - degradation before reaching cell surface
Microarrays

21. Where are cytosolic and organellar proteins made
Read from a fixed starting point as a continuous sequence of bases
SAM
Free ribosomes
Coenzyme A - lipoamide

22. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
IDL
Coenzyme A - lipoamide
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Alpha 1 -6 and alpha 1 -4

23. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
Cofactor for LPL
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Heterochromatin = HighlyCondensed
FMR1 gene - methylation - associated with chromosomal breakage

24. What do DNA topoisomerases do
NADH - NADPH - FADH2
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Creat a nick in the helix to relieave supercoils created during replication
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

25. What is the amino acid precursor for catecholamines
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Phenylalanine
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Inc melt - dec fluidity

26. What happens in vit D excess
4 under the floor
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
EtOH dehydrogenase and acetaldehyde dehydrogenase
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

27. What does vit E def cause
Exons
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
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

28. What is the RDE of de novo pyrimidine synthesis
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Krabbes - galactocerebrosidase - galactocerebroside - AR
Carbomoyl phosphate synthetase II
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora

29. What is the activated carrier for phosphoryl
ATP
APKD1 on chromosome 16
Four
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

30. A small proportion of Down syndrome is due to What two genetic events
Robertsonian translocation and mosaicism
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase

31. Which anticancer drugs work on microtubules
Vincritsine/vinblastine
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
African Americans and Asians
Base + ribose

32. What does desmin stain for
Oligomycin
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Muscle
Alkaptonuria - may have debiliating arthralgias

33. I g fat = ? Kcal
Nine
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE
Diphyllobothrium latum
SnRNPs and other proteins

34. What apolipoproteins are on IDL
Keep glutathione reduced so it can detoxify free radicals and peroxides
Deamination
Metanephrine
B100 and E

35. What is I cell disease
Kwashiorkor - small child with swollen belly
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan
Glycolysis and aerobic respiration
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

36. What happens in carnitine def
NF2 on chromosome 22
Skin
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia

37. What substance in egg whites binds biotin
CG- 3 > AT-2 - More CG content - melting point goes up
Ile - phe - thr - trp
THFs
Avidin

38. What is the Name and fxn of vit B5
Lariat shape in order and remove intron precisely and join 2 exons
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Fasting

39. How do stable (quiescent) cells grow and regenerate and What are examples
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

40. What shuttle is used in fatty acid degredation and What does it move and From where to where
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Carnitine shuttle - acyl - coa from cyto to mito
HVA
Active secretion in lungs and GI - reabsorbs in skin

41. deletion of VHL gene on chromosome 3 leading to hemangioblastomas of retina/cerebellum/medulla bilateral RCC - dz and overexpression product
SnRNPs
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Von hippel lindau - 3
Anchor muscle fibers - primarily in skeletal and cardiac muscle

42. What collagen type is most frequently affected in ehlers danlos and What are common complications
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
III - joint dislocation - anuerysms - organ rupture
Antioxidant - protects RBCs and membrances from free radical damage
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

43. What does a carboxylase do
Seals.
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Adds 2 carbon with the help of biotin
Orotate precursor - with PRPP added later

44. What is the Name and function of vit B2
Pyruvate - NAD+ - CoA
Removal of N or C termal propeptides from zymogens to generate mature proteins
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Glucose 6 phosphatase

45. cardiomegaly - systemic findings leading to early death - dz and enzyme

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46. What does osteogenesis imperfecta causes and why
Night blindness - dry skin
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
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
B100 and E

47. Where is glucose 6 phosphatase found and What does it do
2 rings
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Cartilage - hyaline - vitreous body - nucleus pulposus
In ER - glucose 6- P to glucose

48. What is the source of energy in the fasting state between meals
Adds 2 carbon with the help of biotin
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
1 ring
MRNA

49. What enzyme converts adenine to AMP
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
IMP precursor
Arginine
APRT + PRPP

50. In what cell is collagen synthesis initiated
After day 1
Medial dorsal nucleus of thalamus - mamillary bodies
Fibroblast
Thymic - parathyroid and cardiac