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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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This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Which type of chromatin is less condensed - transcriptionally active - sterically accesible
Euchromatin
Neuralgia
Glucose - 2Pi - 2ADP - 2NAD+
After citruline

2. What does the deletion of the dystrophin gene lead to...
Collagen
Accelearted muscle breakdown
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
Inc Cl - in sweat

3. What are the results of unbalanced translocation
HVA
MRNA
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

4. How do glucagon/epi lead to glycogenolysis
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Acetoacetate and beta hydroxybutyrate
Marasmus - muscle wasting
Liver - also in kidney and gut epithelium

5. What is the fxn of vit K
Promotor - TATA box - and CAAT box - AT rich
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

6. What is the mutation in beckers muscular dystrophy - What is the severity and time of onset
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Cleft palate - cardiac abnl - pregs test
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Mutated dystrophin gene - less severe - adolescence

7. What are cyclin - CDK complexes
Must be both activated and inactivated for cell cycle to progress
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Ketone - methyl
TRNA

8. What is the order of severity for the different types of mutations
N to C
Blood - bone marrown - amniotic fluid - placental tissue
Dopamine beta hydroxylase
Nonsense > missense > silent

9. What is the Name and function of vit B2
Thymic - parathyroid and cardiac
Phosphorylation - glycosylation - hydroxylation
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

10. What does apoB100 do
Binds to LDL receptor - mediates VLDL secretion
Kwashiorkor - small child with swollen belly
NADH - NADPH - FADH2
30 - 50 - 70

11. What does a southern blot use as its sample
Phenytoin - MTX - and sulfonamides
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
DNA

12. What is the origin of replication
African Americans and Asians
Neuralgia
Mediates chylomicron secretion
Particular sequence of DNA where replicatino begins - may be single of multiple

13. What does inc phenylalanine lead to...
Tyrosine
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
1 kind with multiple subunits
Phenylketones in urine

14. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
IDL
Isocitrate dehydrogenase
HMG- CoA reductase
Glucose -6 phosphate

15. What apolipoproteins are on chylomicrons
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
B48 - AIV - CII - E
2pq
DNA

16. What is the Name and fxn of vit B5
B100
30 - glycerol -3- phosphate shuttle
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

17. What is the Name and fxn of vit B12
Exercise: inc NAD/NADH - inc ADP - inc Ca
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
IDL
Huntingtons

18. What are the results of pancreatic insuff in CF
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Cartilage - hyaline - vitreous body - nucleus pulposus
Malabsorption and steatorrhea (ADEK)

19. What 3 amino acids are necessary for purine synthesis
Thymic - parathyroid and cardiac
75 to 90 - cloverleaf
P2 +2pq+ = 1
Glycine - aspartate - glutamine

20. What is Retin A used topically for
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Wrinkles and acne
Inhibits the Na/K pump by binding the K side
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light

21. What happens in vit K def
Free ribosomes
Mediates chylomicron secretion
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Comlex II

22. What is the treatment for orotic aciduria
Cleft palate - cardiac abnl - pregs test
Oral uridine administration
Keep glutathione reduced so it can detoxify free radicals and peroxides
GTP

23. What does lactase deficiency cause
Inc glucagon - inc cAMP - inc PKA
Avidin
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Creat a nick in the helix to relieave supercoils created during replication

24. What tissues have both enzymes of sorbitol metabolism
30 - glycerol -3- phosphate shuttle
1 ring
Inc glucagon - inc cAMP - inc PKA
Liver - ovaries - seminal vesicles

25. What is used to diagnose muscular dystrophies
Glucose - 2Pi - 2ADP - 2NAD+
Inc CPK and muscle biopsy
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

26. What lab value can distinguish orotic aciduria from ornithine transcarbamoylase def?
Poly A polymerase - signal is AAUAA
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
OTC has hyperammonemia - orotic aciduira does not

27. What are cyclins
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Creat a nick in the helix to relieave supercoils created during replication
Adipse tissue stores - keton bodies become the main source of energy fo the brain and heart - after these are depleted - vital protein degradation accelerates - leading to organ failure and death
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes

28. What is the RDE of ketogenesis
APKD1 on chromosome 16
HMG- CoA synthase
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

29. What does a defective Cl channel do
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
PCR - denaturation - annealing - elongation
Hereditary spherocytosis
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

30. What are the only purely ketogenic amino acids
Debranching enzyme
Lysine and leucine
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast

31. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Cyclin dependent kinases;constitutive and inactive
Familial hypercholesterolemia - hyperlipidemia type IIA

32. What co - factors are required for the pyruvated dehydrogenase complex
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
HMG- CoA reductase
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

33. 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
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
FISH
CGG

34. How does cytosine become uracil
CAG
Paclitaxel
Deamination
Mediates chylomicron secretion

35. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
O- oligosaccharaides
Basement membrane or basal lamina
RNA

36. What shuttle is used in fatty acid degredation and What does it move and From where to where
NADPH
Carnitine shuttle - acyl - coa from cyto to mito
Fasting
Free ribosomes

37. What is the rate limiting enzyme in cholesterol synthesis
Carnitine acyltransferase I
HMG- CoA (HMG- CoA to mevalonate
Anchor muscle fibers - primarily in skeletal and cardiac muscle
2pq

38. What does Citrate Is Krebs starting substrate for making oxaloacetate
Activates LCAT
Pyruvate - NAD+ - CoA
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def

39. What is locus heterogeneity and give an example
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
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
Site of steroid synthesis and detoxification of drugs and poisons

40. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Williams syndrome
Terminal regions - tropocollagen
ATP and methionine
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles

41. Which are the basic amino acids
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Protein
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Arg - lys - his - arg is most basic - has has no charge at body pH

42. What is the RDE of gluconeogenesis
Muscle
Fructose 1 -6 bisphosphate
Karyotyping
Arg - lys - his - arg is most basic - has has no charge at body pH

43. What happens in the first stage of collagen synthesis - and Where does it happen
Von hippel lindau - 3
32 - malate aspartate shuttle
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase

44. What occurs to oxaloacetate in starvation and DKA
Transmitted only through mother - all offspring of affected females may show signs of disease
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
CTG
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

45. What are the glucogenic essential amino acids
Carbomoyl phosphate synthetase I
Met - val - arg his
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
HMG- CoA synthase

46. What is the result of vit B5 def
Dermatitis - enteritis - alopecia - adrenal insuff
Inc insulin - dec cAMP - dec PKA
Inhibit DNA gyrase specific for prokaryotic topoisomerase
AR

47. What does a western blot use for its sample
Glutamate
5' to 3'
Protein
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

48. How do odd chain fatty acids participate in gluconeogenesis
Procollagen - triple helix of 3 alpha collagen chains
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
RRNA
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

49. What are the teratogenic effects of vit A and What test must be ordered before starting a woman on isotreitinoin for severe acne
Cleft palate - cardiac abnl - pregs test
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Carnitine acyltransferase I
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells

50. cytoskeletal elements associated with cilia - flagella - mitotic spindle - neurones and centrioles
Adds an inorganic phosphate onto substrate without using ATP
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Microtubules
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase