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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
One
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Chylomicrons
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles

2. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
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
RNA
Promotor - TATA box - and CAAT box - AT rich
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

3. In what cells do the respiratory burst occur
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
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
PMNs
EtOH dehydrogenase and acetaldehyde dehydrogenase

4. What does Ehlers Danlos cause and why
Oxidative and nonoxidative - no ATP produced or used
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Breaks down acyl - coa to acetyl coa groups in mito

5. What is the hardy weinberg allele prevalence
O- oligosaccharaides
Site of steroid synthesis and detoxification of drugs and poisons
Adds an inorganic phosphate onto substrate without using ATP
P+q = 1

6. What are the findings with homocystinuria and What amino acid is needs to be supplemented
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Dec methionine - inc cystiene - inc B12/folate

7. How do aminoglycosides work
By inhibiting formation of the initiation complex and cause misreading of mRNA
Inc melt - dec fluidity
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

8. central and peripheral demyelination with ataxia and dementia
Blood - bone marrown - amniotic fluid - placental tissue
Neurofibromatosis type 1 (von Recklinghausens disease)
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Binds 50S - blocking translocation

9. What substances directly inhibit electron transport chain
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Rotenone - CN- - antimycin A - CO
Proton gradient
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

10. What enzyme degrades a small amount of glycogen in lysosomes
Dermatitis - alopecia - enteritis
Alpha 1 -4 glucosidase
Vit K antagonist
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP

11. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
Intermediate filaments
Familial hypercholesterolemia - hyperlipidemia type IIA
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
Infection - free radicals generated by inflammatory response

12. What happens in vit D def
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Hereditary spherocytosis
IMP precursor
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)

13. A small proportion of Down syndrome is due to What two genetic events
Robertsonian translocation and mosaicism
Acetyl - CoA carboxylase (ACC)
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
X- linked recessive

14. What stretch of DNA that alters gene expression by binding of transcription factors
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Enhancers
Proline and lysine - vit C
Acetly- CoA - CO2 - NADH

15. What does Citrate Is Krebs starting substrate for making oxaloacetate
Cofactor for LPL
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15

16. How do odd chain fatty acids participate in gluconeogenesis
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

17. What is the smallest mutation a mircoarray can detect
CAG
Disease
SNP
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

18. Where is vit A found in the diet
Inhibits 50S peptidyltransferase
Liver and leafy veggies
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Defect in fibrillin

19. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Oxalacetate
Foliage - small reserve in liver - eat green leaves
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

20. What is locus heterogeneity and give an example
Makes RNA primer on which DNA poly III can initiate replication
Glutamate
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Same as sprint + OXPHOS

21. What does vit C def cause
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Mediates chylomicron secretion
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Liver - ovaries - seminal vesicles

22. What defects characterize DiGeorge syndrome
Procollagen - triple helix of 3 alpha collagen chains
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Neural tube
Thymic - parathyroid and cardiac

23. What ribosomes do eukaryotes have
Anchor muscle fibers - primarily in skeletal and cardiac muscle
75 to 90 - cloverleaf
Superoxide dismutase
40 - 60 - 80

24. What is the amino acid precuror for creatine - urea and nitric oxide
Glycine - aspartate - glutamine
Disease
Blood - bone marrown - amniotic fluid - placental tissue
Arginine

25. What causes Marfan syndrome
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Defect in fibrillin
FAP
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

26. What is the Name and fxn of vit B5
Glycogenolysis to form glucose
Malabsorption and steatorrhea (ADEK)
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
ATP and methionine

27. recurrent pulmonary infxns in CF are due to what organisms
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Pseudomonas and s aureus
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase

28. What is the source of energy in the fasting state between meals
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Connective tissue
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

29. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
F16BP
Acetyl - CoA
Makes RNA primer on which DNA poly III can initiate replication
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles

30. What does aminoacyl tRNA synthetase do the AA before and after it binds to tRNA - and what happens if it's the wrong the match
CTG
Scrutinizes - hydrolyzes the bond
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

31. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Tryptophan
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes

32. What does the ELISA test for
Niacin - constituent of NAD and NADP - derived from tryptophan
Fructose 1 -6 bisphosphate
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)

33. What occurs to oxaloacetate in starvation and DKA
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding
Mebendazole/thiabendazole
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible

34. What enzyme converts adenine to AMP
APRT + PRPP
Glycine - aspartate - glutamine
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
GAA

35. What rxn creates ATP
After citruline
Eu - methionine - pro - formyl - methionine
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

36. hepatosplenomegaly - aseptic necrosis of femur - bone crisis - MACS that look like crumpled tissue paper

37. What is the exception to genetic redundancy
9+2 arrangement of microtubules
Methionine encode by only 1 codon (AUG)
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
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

38. What is trimming
Oral uridine administration
Tropoelastin with fibrillin scafolding
CFTR gene - 7 - Phe 508
Removal of N or C termal propeptides from zymogens to generate mature proteins

39. What does the golgi do to sugars in proteoglycans and of selected tyrosine on proteins
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Same AA - often base change in 3rd position of codon (tRNA wobble)
Sulfation
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

40. peripheral neuropathy of hands/feet - angiokeratomas - CV/renal disease - dz - def enzyme - acc substrate - inherit
Tryptophan
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Colchicine
Inhibits the Na/K pump by binding the K side

41. This is the site where negative regulators bind
Silencers
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood

42. What are cyclins
Pseudomonas and s aureus
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
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Removal of N or C termal propeptides from zymogens to generate mature proteins

43. What are the glucogenic essential amino acids
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Dec DNA - dec lymphos leads to SCID
Met - val - arg his
Rotenone - CN- - antimycin A - CO

44. What is the wernicke - korsakoff clinical picture
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
By inhibiting formation of the initiation complex and cause misreading of mRNA
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss

45. What is the function of folic acid
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
By inhibiting formation of the initiation complex and cause misreading of mRNA
1 -25 OH2 D3 = calcitriol
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

46. What are the products for glycolysis
Actin and myosin
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Schilling test
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O

47. In eukaryotes - What does RNA poly II make
MRNA
Arg and his inc in histones Which bind negatively charged DNA
Ile - phe - thr - trp
Attachment of ubiquitin to defective proteins tag them for breakdown

48. What is the activated carrier for aldehyddes
TTP
ATP
Deamination
Initiate chains

49. What is the longest time of RNA and shortest
MRNA - tRNA
Inhibits RNA polymerase II - found in death cap mushrooms
Glucose - 2Pi - 2ADP - 2NAD+
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

50. progressive neurodegeneration - developmental delay - cherry red spot on macula - lysosomes with onion skin - NO hepatosplenomegaly
No
1 kind with multiple subunits
P2 +2pq+ = 1
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR