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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. The pyruvate dehydorgenase complex serves In what reaction: reactants
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
SnRNPs
Metanephrine
Pyruvate - NAD+ - CoA

2. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Tuberous sclerosis
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
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

3. How do tetracyclines work
RNA
Anabolic processes as a supply of reducing equivalents
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Particular sequence of DNA where replicatino begins - may be single of multiple

4. Which bond is stronger AT or CG and why? What is the laboratory consequence of this?
Acetyl - CoA to malonyl - CoA (2C to 3C)
No
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
CG- 3 > AT-2 - More CG content - melting point goes up

5. What does osteogenesis imperfecta causes and why
Deamination
CTG
Leu - lys
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

6. What is the Hardy Weinberg disease prevalence equation
Lysine and leucine
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
Nine
P2 +2pq+ = 1

7. In what cells do the respiratory burst occur
PMNs
Result from phagocytic removal of heinz bodies my macs - G6PD def
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
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels

8. What does PURe As Gold and CUT The Py stand for
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Hereditary spherocytosis
ATP hyrdolysis couple to energetically unfavorable rxns
Purines= A - G pyrimidine = C - T (U)

9. What is the function of Zinc
THFs
Removal of N or C termal propeptides from zymogens to generate mature proteins
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
APRT + PRPP

10. What is the RDE of TCA cycle
B100 and E
Phenytoin - MTX - and sulfonamides
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Isocitrate dehydrogenase

11. Giving folate during early pregnancy is important to prevent what birth defects
25OHD3
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
HMG- CoA reductase
Neural tube

12. What does fomepizole do
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Alpha - ketoglutarate dehydrogenase complex

13. what gene is implicated in fragile X syndrome - and What is the mutation
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
FMR1 gene - methylation - associated with chromosomal breakage
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
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

14. What is the active form of vit D
Sucrose = glucose + fructose - lactose = glucose + galactose
1 -25 OH2 D3 = calcitriol
Oxalacetate
Inhibit DNA gyrase specific for prokaryotic topoisomerase

15. Which antifungal drugs work on microtubules
Epithelial cells
Krabbes - galactocerebrosidase - galactocerebroside - AR
Griseofulvin
ATP

16. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Neuralgia
Glucose 6 phosphatase

17. What are pyrimidines made from
Carbomoyl phosphate synthetase II
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Orotate precursor - with PRPP added later
APC on chromosome 5

18. What causes patau's syndrome and What is it
Deamination
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
III - joint dislocation - anuerysms - organ rupture
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

19. pyruvate carboxylase catalyzes what rxn
Pyruvate to oxaloacetate (3C to 4C)
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
GAA
Antigen - antibody reactivity - can look for antigen or antibody in patients blood

20. What causes B12 def
Males are infertile due to bilateral absence of vas deferens
NADPH
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Inc permeability of membrane causing a dec in proton gradient and inc in O2 consumption - ATP synthesis stops - but electron transport continues to produce heat

21. What is anticipation and give an example
Targets the proteins for lysosome
ATP hyrdolysis couple to energetically unfavorable rxns
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
They yield only acetyl - CoA equivalents

22. What does an umabiguous genetic code refer to...
Palate - facial and cardiac defects
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Each codon specifies only 1 amino acid

23. What is mosaicism and give an example
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females
Mitochondria

24. What metabolic rxns occur in the cytoplasm
DNA
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
RNA poly II

25. What are the 3 AR forms of homocystinuria
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
F16BP
Mebendazole/thiabendazole

26. What is the initial transcript called and What is the capped and tailed transcript called
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Oral uridine administration
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Facial flushing

27. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Only processed RNA
Terminal regions - tropocollagen
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Collagen

28. what disease can cause pellagra
Fructose 1 -6 bisphosphate
Microarrays
Elastase - inhibited by alpha1 antitrypsin
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

29. What metabolic rxns occur in the mitochondria
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
CG- 3 > AT-2 - More CG content - melting point goes up
PCR - denaturation - annealing - elongation
Microarrays

30. What apolipoproteins are on chylomicrons
Binds to LDL receptor - mediates VLDL secretion
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
B48 - AIV - CII - E
Proline and glycine (non glycosylated forms)

31. What metabolic rxns occur in both the cytoplasm and mitochondria
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Fasting
Dermatitis - enteritis - alopecia - adrenal insuff

32. bilateral acoustic schwannomas - juvenile cataracts
Activates LCAT
NF2 on chromosome 22
Cytosol
Glycogen and FFA oxidation; glucose conserved for final sprinting

33. What do the single stranded binding proteins do
Prevent strands from reannealing
Mitochondria
ATP and alanine
TTP

34. What is the fxn of vit E
ADPKD
Neurofibromatosis type 1 (von Recklinghausens disease)
Glycogen phosphorylase
Antioxidant - protects RBCs and membrances from free radical damage

35. What is the rate determining enzyme (RDE) of glycolysis
Glycogen and FFA oxidation; glucose conserved for final sprinting
Must be both activated and inactivated for cell cycle to progress
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Phosphofructokinase 1

36. What is NADPH used for
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Glycogen synthase
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Anabolic processes as a supply of reducing equivalents

37. Where are FADH2 electrons transferred to...
Comlex II
Change resulting in early stop codon
Liver - also in kidney and gut epithelium
Alcohol version of glucose - can trap glucose in cell - aldose reductase

38. What does the addition of mannose -6 phosphate do
Targets the proteins for lysosome
P2 +2pq+ = 1
Flagella - cilia - mitotic spindles
Arginine

39. What neuroanatomical strutures are injured in wernicke - korsakoff
Night blindness - dry skin
Medial dorsal nucleus of thalamus - mamillary bodies
30 - glycerol -3- phosphate shuttle
CTG

40. congenital microdeletion of short arm of chromosome 5 with microcephaly - moderate to severe mental retardation - high pitched crying/meying - epicanthal folds - cardiac abnl
Hypoxanthine to xanthing and xanthine to uric acid
Cri du chat
By inhibiting formation of the initiation complex and cause misreading of mRNA
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

41. What does the golgi add to serine and threonine residues
Hypoxanthine to xanthing and xanthine to uric acid
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
O- oligosaccharaides
Acetly- CoA - CO2 - NADH

42. decreases In what substances can cause PKU
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Diphyllobothrium latum
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

43. What liberates glucose from glucose 6 P
Phenylethamolamine N methyl transferase
Liver - also in kidney and gut epithelium
Glucose 6 phosphatase
Comlex II

44. What converts NE to epi
Heterochromatin = HighlyCondensed
Inhibits the Na/K pump by binding the K side
Phenylethamolamine N methyl transferase
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond

45. What converts DOPA to dopamine
PFK - rate limiting enzyme
Inhibits 50S peptidyltransferase
Dopa decarboxylase
In ER - glucose 6- P to glucose

46. How do you diagnose CFTR
Prevent strands from reannealing
Protein kinase A
Adds 2 carbon with the help of biotin
Inc Cl - in sweat

47. What does hartnups disease cause
Superoxide dismutase
Stored ATP - creatine phosphate - anaerobic glycolysis
Activates LCAT
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra

48. What is the function and name of vit B6
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
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
Malapsorption syndromes like sprue or CF or mineral oil intake
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

49. What do DNA topoisomerases do
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Creat a nick in the helix to relieave supercoils created during replication
Free ribosomes
Q -

50. What does Citrate Is Krebs starting substrate for making oxaloacetate
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
VMA
Tryosine hydroxylase
Schwann cells - lens - retina - kidneys