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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 substances directly inhibit electron transport chain
Orotate precursor - with PRPP added later
HMG- CoA reductase
Neurofibromatosis type 1 (von Recklinghausens disease)
Rotenone - CN- - antimycin A - CO

2. What does a dehydrogenase do
Grows slowly - collapses quickly
After day 1
Oxidizes substrate
Deamination

3. What is the physiologic role of dystrophin
Fructose 1 -6 bisphosphate
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Mebendazole/thiabendazole
Anchor muscle fibers - primarily in skeletal and cardiac muscle

4. What is loss of heterozygosity and give an example
HMP shunt
Proline and glycine (non glycosylated forms)
Phenytoin - MTX - and sulfonamides
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

5. pyruvate carboxylase catalyzes what rxn
Pyruvate to oxaloacetate (3C to 4C)
RER
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
BOne

6. What are the water soluble vitamins - which ones are stored
FISH
Flank pain - hematuria - HTN - progressive renal failure
Marfans
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

7. What do neurofilaments stain for
Neurons
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
N to C
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

8. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Essential fructosuria - fructokinase AR
THFs
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Schilling test

9. What happens with wet beriberi
High output cardiac failure - dilated cardiomyopathy - edema
Phenylalanine
Accelearted muscle breakdown
Dermatitis - alopecia - enteritis

10. What does desmin stain for
Mucus secreting globlet cells and antibody secreting plasma cells
Muscle
Reads usual codon but inserts wrong AA
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

11. What is the most abundant protein in the body
CGG
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Oligomycin
Collagen

12. What are the 4 assumption of the Hardy Weinberg law
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
IMP precursor
Flank pain - hematuria - HTN - progressive renal failure
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

13. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Tropoelastin with fibrillin scafolding
MEN - 2A and 2B with ret gene
Alkaptonuria - may have debiliating arthralgias
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty

14. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
Supply sufficient glucose to brain and RBCs and to preserve protein
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Zero
LDL

15. What are the irreversible enzymes of gluconeogenesis
Neimann - pick - sphingomyelinase - sphingomyelin - AR
TTP
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Bind 30s subunit preventing attachment of aminoacyl - tRNA

16. What tissues have only aldose reductase
RNA poly II
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Schwann cells - lens - retina - kidneys

17. What is the RDE of the HMP shunt
Lysine and arginine
Glucose 6 phosphate dehydrogenase (G6PD)
ATP
Neural tube

18. The pyruvate dehydrogenase complex serves In what reaction: products
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Failure to track objects or develop a social smile
Acetly- CoA - CO2 - NADH
Ca/calmodulin in muscle to coordinate with muscle activity

19. What is the defect in fructose intolerance and What does it cause
Alkaptonuria - may have debiliating arthralgias
Malonyl coa
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Infection - free radicals generated by inflammatory response

20. What enzyme converts phenylalanine to tyrosin
Catabolic processes to carry reducing equivalents away as NADH
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Phenylalanine hydroxylase

21. Type I collagen
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Fed
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
ATP and methionine

22. What is the activated carrier for phosphoryl
Mucus secreting globlet cells and antibody secreting plasma cells
ATP
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Inhibits the Na/K pump by binding the K side

23. Which direction does dynein go
Microarrays
Consesus sequenec of base pairs
One
Post to neg

24. What does the golgi apparatus do on asparagine
Hereditary spherocytosis
Inhibit DNA gyrase specific for prokaryotic topoisomerase
The triphosphate bond
Modifies N- oligosaccharides

25. What is the active form of vit D
Deamination
1 -25 OH2 D3 = calcitriol
Microarrays
Hypoxanthine to xanthing and xanthine to uric acid

26. What does a carboxylase do
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
Cartilage - hyaline - vitreous body - nucleus pulposus
Adds 2 carbon with the help of biotin
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

27. What are the findings in PKU
Tyrosine
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Two

28. What is the pathway in the fasting state leading to inc FBPase -2 and dec PFK-2
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Ribos first then deoxyribos with ribonucleotide reductase
No - its non homologous
Inc glucagon - inc cAMP - inc PKA

29. What is regeneration of methionine depedent on...
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
B12 and folate
Glycine - aspartate - glutamine
B100 and E

30. What is Gowers maneuver
HMG- CoA (HMG- CoA to mevalonate
Assistance of upper extremities to stand up
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O

31. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Actin and myosin
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

32. Which are the acidic amino acids
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Asp and Glu
GTP
Inhibit DNA gyrase specific for prokaryotic topoisomerase

33. How do stable (quiescent) cells grow and regenerate and What are examples
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
APRT + PRPP
Binds to LDL receptor - mediates VLDL secretion
Proline and glycine (non glycosylated forms)

34. 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
Two
Inc dicarboxylic acids - dec in glucose and ketones
Carbomoyl phosphate synthetase I

35. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Euchromatin
Uses ATP to add high energy phophate group onto substrate
Facial flushing
Marasmus - muscle wasting

36. Fluorescent DNA or RNA probe binds to specific gene of interest - used for specific localization of genes and direct visualization of anomalies - like microdeletions - at molecular level
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Scrutinizes - hydrolyzes the bond
FISH
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

37. In what cell is collagen synthesis initiated
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Fibroblast
CG- 3 > AT-2 - More CG content - melting point goes up
Protein kinase A

38. What is anticipation and give an example
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
Microtubules
Protective against malaria
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons

39. What does Citrate Is Krebs starting substrate for making oxaloacetate
Grows slowly - collapses quickly
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Arg - lys - his - arg is most basic - has has no charge at body pH
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA

40. How many rings do purines have
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
2 rings
Fructose 1 -6 bisphosphate
Nissl body - enzyme and NTs

41. What feedback inhibits hexokinase
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Glucose -6 phosphate
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Polycystic liver disease - berry aneurysm - mitral valve prolapse

42. What test is used for B12 def
Fructose 1 -6 bisphosphate
AMP - fructose 2 -6 BP
Schilling test
VMA

43. What converts limit dextran to glucose
Debranching enzyme
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
RNA
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

44. What is the amino acid precursor for porphyrin and heme
Glycine
Williams syndrome
More than 1 codon may code for the same amino acid
Krabbes - galactocerebrosidase - galactocerebroside - AR

45. The pyruvate dehydorgenase complex serves In what reaction: reactants
Pyruvate - NAD+ - CoA
Ribose 5- P to PRPP
Stored ATP - creatine phosphate - anaerobic glycolysis
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

46. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Inc insulin - dec cAMP - dec PKA
Chylomicrons
Peroxide

47. cytoskeletal elements associated with cilia - flagella - mitotic spindle - neurones and centrioles
Microtubules
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Dec methionine - inc cystiene - inc B12/folate

48. What are ketone bodies made from - where are they metabolized and how are they excreted
Pseudomonas and s aureus
Hypoglycemia
Glycogenolysis to form glucose
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine

49. What does a kinase do
LDL
Uses ATP to add high energy phophate group onto substrate
B100
B100 and E

50. congenital microdeletion of short arm of chromosome 5 with microcephaly - moderate to severe mental retardation - high pitched crying/meying - epicanthal folds - cardiac abnl
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Cri du chat
LCAT (lecithin cholesterol acyltransferase)
Antibiotic use or excessive ingestion of raw eggs