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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 enzyme adds Cl - to the H202 to makes bleach
HMP shunt
Carbomoyl phosphate synthetase II
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Myeloperoxidase

2. Which tumor suppresors inhibit G1 to S progression - where mutations result in unrestrained growth
Rb and p53
Dermatitis - glossitis - and diarrhea
Actin and myosin
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

3. What does a northern blot use as its sample
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
RNA
Acetly- CoA - CO2 - NADH
Y shaped region along the DNA template where leading nad lagging strands are synthesized

4. In prokaryotes - What does makes the different types of RNA
EtOH dehydrogenase and acetaldehyde dehydrogenase
Vincritsine/vinblastine
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
1 kind with multiple subunits

5. What does cytokeratin stain for
Neural tube
Fed
Epithelial cells
African Americans and Asians

6. What other complex is similar to the pyruvate dehydrogenase complex in that it has the same co - factors and generates succinyl - CoA
VMA
3' end (with CCA)
Alpha - ketoglutarate dehydrogenase complex
Malabsorption and steatorrhea (ADEK)

7. characterize x linked recessive
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
Cri du chat
Carbomoyl phosphate synthetase II
Defect in fibrillin

8. Which are the basic amino acids
Arg - lys - his - arg is most basic - has has no charge at body pH
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Flagella - cilia - mitotic spindles
PMNs

9. Why is G6PD def more common among patients of african decent
Protective against malaria
THFs
Euchromatin
5' of the incoming nucleotide

10. decreases In what substances can cause PKU
Mediates chylomicron secretion
ATP
Mutated dystrophin gene - less severe - adolescence
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor

11. Type I collagen
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Active secretion in lungs and GI - reabsorbs in skin
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

12. What fxn does glucokinase serve in the liver
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Zero
Adds an inorganic phosphate onto substrate without using ATP
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

13. In which state is FBPase -2 active
Fasting
CAG - 4
Flank pain - hematuria - HTN - progressive renal failure
Antigen - antibody reactivity - can look for antigen or antibody in patients blood

14. Gene imprinting implies that How many alleles are active at a single locus
One
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Glucose -6 phosphate
Protein kinase A

15. What does biotin def cause
Intermediate filaments
Dermatitis - alopecia - enteritis
SnRNPs
1 kind with multiple subunits

16. What is the activated carrier for phosphoryl
ATP
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Flank pain - hematuria - HTN - progressive renal failure
Cartilage - hyaline - vitreous body - nucleus pulposus

17. What happens in vit K def
Phenylethamolamine N methyl transferase
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Alpha 1 -4 glucosidase
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

18. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Cre - lox system
Dec methionine - inc cystiene - inc B12/folate
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

19. what disease can cause pellagra
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Orotate precursor - with PRPP added later
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

20. What are the priorities for the body in fasting and starvation
Males are infertile due to bilateral absence of vas deferens
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Supply sufficient glucose to brain and RBCs and to preserve protein

21. What apolipoproteins are on chylomicrons
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
B48 - AIV - CII - E
NAD+

22. What does beta oxidation do and Where does it occur
Tropoelastin with fibrillin scafolding
Breaks down acyl - coa to acetyl coa groups in mito
Tuberous sclerosis
ATP and methionine

23. What does apoCII do
Thymic - parathyroid and cardiac
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Cofactor for LPL
Phenylalanine

24. What is the most abundant type of RNA
Vit K antagonist
Microtubules
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
RRNA

25. How does cytosine become uracil
Deamination
Acetyl - CoA to malonyl - CoA (2C to 3C)
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
RER

26. Type I bone
BOne
Oxidizes substrate
Proline and glycine (non glycosylated forms)
Adenosine to inosine

27. in a 100 meter sprint Where does energy come from
F16BP
Stored ATP - creatine phosphate - anaerobic glycolysis
Tyrosine
Nonsense > missense > silent

28. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Evident in first few days of life - can present last onest - excess carbamoyl phosphate converted to orotic acid - orotic acid in blood and urine - dec BUN and symptoms of hyerpammonemia
Muscle
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

29. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
Alpha 1 -4 glucosidase
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
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Inc intestinal absorption fo calcium and phosphate - inc bone resorption

30. What is the most abundant protein in the body
Collagen
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
Isocitrate dehydrogenase
Mitochondria

31. Which are the acidic amino acids
EtOH dehydrogenase and acetaldehyde dehydrogenase
Asp and Glu
Lysine and arginine
Unwinds DNA template at replcation fork

32. What are the findings in Down's syndrome
Hypoxanthine to xanthing and xanthine to uric acid
Metanephrine
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
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

33. What substance in egg whites binds biotin
F16BP
Autosomal recessive diseases
Avidin
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs

34. How does ethanol induce hypoglycemia
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
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
Creat a nick in the helix to relieave supercoils created during replication
DsRNA promotes degradation of target mRNA knocking down gene expression

35. What drugs can cause folate def
9+2 arrangement of microtubules
Phenytoin - MTX - and sulfonamides
Same as sprint + OXPHOS
Neural tube

36. What is the name is fxn of vit B3
Fibroblast
Glucose 6 phosphate dehydrogenase (G6PD)
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Niacin - constituent of NAD and NADP - derived from tryptophan

37. Accurate base pairing is required only in the first two nucleotide positions of an mRNA codon - so conds differeing in the 3rd position may code for the same tRNA/AA due to degenerate genetic code
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Elastase - inhibited by alpha1 antitrypsin
Wobble

38. What is variable expression and What is an example
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Removes phosphate group from substrate
Unwinds DNA template at replcation fork
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine

39. What happens in vit D excess
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Kidney - ears - eyes
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Abnormal protein folding - degradation before reaching cell surface

40. What is the defect in II A familial hypercholesterolemia
Familial hypercholesterolemia - hyperlipidemia type IIA
Cyclin dependent kinases;constitutive and inactive
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
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

41. What are the characteristics of angelmans syndrome and How does it occur
17 - 17 letters in von Recklinghausen
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Zero
Glycine - aspartate - glutamine

42. When are glycogen reserves depleted
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Degredation of TG circulating in chylomicrons and VLDLs
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
After day 1

43. ADPKD is associated with What additional conditions
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Polycystic liver disease - berry aneurysm - mitral valve prolapse

44. What converts DOPA to dopamine
Disorder of aromatic amino acid metabolism
Creat a nick in the helix to relieave supercoils created during replication
Karyotyping
Dopa decarboxylase

45. What is a missense mutation
Ca/calmodulin in muscle to coordinate with muscle activity
African Americans and Asians
Changed AA (convservative - new AA is similar in chemical structure)
Failure to track objects or develop a social smile

46. congenital microdeletion of short arm of chromosome 5 with microcephaly - moderate to severe mental retardation - high pitched crying/meying - epicanthal folds - cardiac abnl
Cri du chat
Alanine
Active secretion in lungs and GI - reabsorbs in skin
UDP glucose pyrophosphorylase

47. What is axonemal dynein
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Familial hypercholesterolemia - hyperlipidemia type IIA
Alpha and beta tubulin - dimers have two GTP bound
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets

48. 90% of ADPKD cases are due to a mutation In what gene
APKD1 on chromosome 16
RNA poly II
FMR1 gene - methylation - associated with chromosomal breakage
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

49. What happens at the smooth ER
Inhibits 50S peptidyltransferase
Site of steroid synthesis and detoxification of drugs and poisons
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)

50. What does inc phenylalanine lead to...
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Poly A polymerase - signal is AAUAA
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Phenylketones in urine