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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 apolipoproteins are on IDL
B100 and E
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Oxidative and nonoxidative - no ATP produced or used
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells

2. What are the results of pancreatic insuff in CF
B-100 - CII and E
No - its non homologous
Malabsorption and steatorrhea (ADEK)
Terminal regions - tropocollagen

3. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Exercise: inc NAD/NADH - inc ADP - inc Ca
Dec DNA - dec lymphos leads to SCID
Transfers methyl units
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

4. What is the breakdown product of NE
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Specific glycosylases - AP endonuclease
Biotin
VMA

5. What are the mRNA stop codons
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Infection - free radicals generated by inflammatory response
UGA - UAA and UAG
Dopa decarboxylase

6. In which state is PFK-2 active
Fed
Assistance of upper extremities to stand up
Oxidizes substrate
Arg - lys - his - arg is most basic - has has no charge at body pH

7. What chromosome is the NF gene on...
Methionine encode by only 1 codon (AUG)
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Rb and p53
17 - 17 letters in von Recklinghausen

8. What is the Name and fxn of vit B5
Cre - lox system
Vincritsine/vinblastine
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Basement membrane or basal lamina

9. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Acetoacetate and beta hydroxybutyrate
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

10. What does apoB100 do
FMR1 gene - methylation - associated with chromosomal breakage
Binds to LDL receptor - mediates VLDL secretion
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Phosphorylation - glycosylation - hydroxylation

11. How is orotic aciduria inherited
AR
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Transmitted through both parents - affected mother may have affected children - affected father will have affected children

12. Mediates reverse cholesterol transport from periphery to liver - acts as respository for apoC an apoE - secreted from both liver and small intestine
Tyrosine
HDL
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Seals.

13. Acetyl - CoA carboxylase catalyzes what rxn
Acetyl - CoA to malonyl - CoA (2C to 3C)
Schwann cells - lens - retina - kidneys
Citrate - acetyl coa from mito to cyto
Degradation of TG remaining in IDL

14. What is the order of severity for the different types of mutations
Nonsense > missense > silent
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Oxidizes substrate
RRNA

15. What ribosomes do eukaryotes have
Protective against malaria
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Lysine and arginine
40 - 60 - 80

16. What is the complication of cystinuria
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Degradation of TG remaining in IDL
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins

17. What defects characterize DiGeorge syndrome
Thymic - parathyroid and cardiac
Epithelial cells
Stored ATP - creatine phosphate - anaerobic glycolysis
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR

18. What liberates glucose from glucose 6 P
Intermediate filaments
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Flagella - cilia - mitotic spindles
Glucose 6 phosphatase

19. What does CATCH 22 stand for and What causes is...
Glutamine PRPP amidotransferase
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

20. What is sorbitol - how and why is it made
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Alcohol version of glucose - can trap glucose in cell - aldose reductase
75 to 90 - cloverleaf
Fed

21. What does amino acid catabolsim results in the formation of what?
ATP - citrate
Skin
Carnitine shuttle - acyl - coa from cyto to mito
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

22. What happens in a B12 def
2 rings
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Arg and his inc in histones Which bind negatively charged DNA
Fed

23. What is trimming
Removal of N or C termal propeptides from zymogens to generate mature proteins
Liver hepatocytes and steroid producing cells of the adrenal cortex
Schwann cells - lens - retina - kidneys
Oxidizes substrate

24. What is uniparental disomy
Alpha 1 -4 glucosidase
Inc melt - dec fluidity
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Isocitrate dehydrogenase

25. What is the smallest mutation a mircoarray can detect
Acetyl - CoA to malonyl - CoA (2C to 3C)
SNP
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Degradation of TG remaining in IDL

26. What is the RDE of glycogenolysis
Protective against malaria
Coenzyme A - lipoamide
Glycogen phosphorylase
Medial dorsal nucleus of thalamus - mamillary bodies

27. Where is hexokinase found - What is its Km and Vmax and what uninduces it
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Lysine and arginine
UGA - UAA and UAG

28. congenital microdeletion of long arm of chromosoe 7 with findings of elfin facies - mental retardation - hypercalcemia - well developed verbal skills - extreme friendliness with strangers - cardiovascular problems
Williams syndrome
HMG- CoA (HMG- CoA to mevalonate
4 under the floor
TRNA

29. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Avidin
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses

30. What leads to the deletion of the dystrophin gene in duchenne's muscular dystrophy
Neurons
X linked frame shif mutation
Biotin
Thymic - parathyroid and cardiac

31. What are CDKs
Core proteins
Creat a nick in the helix to relieave supercoils created during replication
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Cyclin dependent kinases;constitutive and inactive

32. Which phase of the HMP shunt is reversible and Which is irreversible
Hypoxanthine to xanthing and xanthine to uric acid
Oxidizes substrate
Oxidative is irreversible
Inhibit DNA gyrase specific for prokaryotic topoisomerase

33. What is the activated carrier for methyl groups
SAM
Paclitaxel
Result from phagocytic removal of heinz bodies my macs - G6PD def
Ca/calmodulin in muscle to coordinate with muscle activity

34. What defects characterize velocardiofacial syndrome
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
More than 1 codon may code for the same amino acid
Palate - facial and cardiac defects
Elastase - inhibited by alpha1 antitrypsin

35. What happens on the nonoxidative arm of the HMP shunt and What is the key enzyme and cofactor
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Citrate - acetyl coa from mito to cyto
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Initiate chains

36. How does abetalipoproteinemia present and What is the defect
Carbomoyl phosphate synthetase II
Mucus secreting globlet cells and antibody secreting plasma cells
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
DsRNA promotes degradation of target mRNA knocking down gene expression

37. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Disorder of aromatic amino acid metabolism
VMA
Myeloperoxidase
CFTR gene - 7 - Phe 508

38. What does hormone sensitive lipase do
Creat a nick in the helix to relieave supercoils created during replication
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Degradation of TG stored in adipocytes
Degradation of TG remaining in IDL

39. What does vit C def cause
Protein
Antibiotic use or excessive ingestion of raw eggs
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Ca/calmodulin in muscle to coordinate with muscle activity

40. How are the many staggered tropocollagen molecules reinforced
Glucose -6 phosphate
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Covalent cross - linking by lysyl oxidase to make collagen fibrils
After citruline

41. What is the source of energy in the fasting state between meals
X linked frame shif mutation
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

42. What is the function of Zinc
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Wrinkles and acne

43. What does GFAP stain for
Neuralgia
After citruline
Only processed RNA
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia

44. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
Neurofibromatosis type 1 (von Recklinghausens disease)
Heterochromatin = HighlyCondensed
Site of steroid synthesis and detoxification of drugs and poisons
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

45. What do def in in enzymes of gluconeogenesis cause
Keep glutathione reduced so it can detoxify free radicals and peroxides
HMP shunt
Hypoglycemia
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

46. How do fluoroquinolones work
Phosphofructokinase 1
Only processed RNA
Inhibit DNA gyrase specific for prokaryotic topoisomerase
FISH

47. How does cytosine become uracil
OTC has hyperammonemia - orotic aciduira does not
Deamination
P2 +2pq+ = 1
Proline and lysine - vit C

48. What are the products for glycolysis
Neither of 2 alleles is dominant - blood groups
1 ring
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Glucose - 2Pi - 2ADP - 2NAD+

49. What is the rate limiting enzyme in cholesterol synthesis
HMG- CoA (HMG- CoA to mevalonate
Stored ATP - creatine phosphate - anaerobic glycolysis
Dopamine beta hydroxylase
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

50. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
By inhibiting formation of the initiation complex and cause misreading of mRNA
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Nissl body - enzyme and NTs
Type II