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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. What apolipoproteins are on chylomicrons
Degradation of TG stored in adipocytes
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
B48 - AIV - CII - E

2. What two cells are particularly rich in RER
1 -25 OH2 D3 = calcitriol
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Targets the proteins for lysosome
Mucus secreting globlet cells and antibody secreting plasma cells

3. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Targets the proteins for lysosome
Type II
APRT + PRPP

4. Gene imprinting implies that How many alleles are active at a single locus
Active secretion in lungs and GI - reabsorbs in skin
One
APC on chromosome 5
Dec DNA - dec lymphos leads to SCID

5. What is the amino acid precursor for catecholamines
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
Bruton's agammaglobulinemia - wiskott - aldrich - fabrys disease - G6PD def - ocular albinism - Lesch - Nyhan syndrome - Duchenne and Becker Muscular Dystrophy - hunter's syndrome - hemophilia A and B
Phenylalanine
Inhibits RNA polymerase II - found in death cap mushrooms

6. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Glucose -6 phosphate
Read from a fixed starting point as a continuous sequence of bases
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

7. How many nucTIDEs is a tRNA and What does the secondary sturcture form
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
75 to 90 - cloverleaf
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

8. trinucleotide repeat for huntingtons
CAG
Arg - lys - his - arg is most basic - has has no charge at body pH
BOne
The triphosphate bond

9. What do the single stranded binding proteins do
Cre - lox system
Binds 50S - blocking translocation
LCAT (lecithin cholesterol acyltransferase)
Prevent strands from reannealing

10. What is axonemal dynein
Phosphorylation - glycosylation - hydroxylation
Dermatitis - glossitis - and diarrhea
ATP
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets

11. What is the activated carrier for Co2
Attachment of ubiquitin to defective proteins tag them for breakdown
P2 +2pq+ = 1
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Biotin

12. What lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Pyruvate - NAD+ - CoA
PCR - denaturation - annealing - elongation
B100 and E

13. What is DNA cloning and How do you do it?
Removal of N or C termal propeptides from zymogens to generate mature proteins
Marfans
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
2pq

14. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Dec DNA - dec lymphos leads to SCID
Glucose -6 phosphate
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
AR

15. What enzyme converts phenylalanine to tyrosin
Each codon specifies only 1 amino acid
Phenylalanine hydroxylase
Phosphofructokinase 1
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

16. In which state is FBPase -2 active
Wrinkles and acne
OTC has hyperammonemia - orotic aciduira does not
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Fasting

17. What happens to oxaloacetate in alcholism
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Glycogen phosphorylase
Dopa decarboxylase

18. What are possilbe presentation for galactokinase def
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Failure to track objects or develop a social smile

19. What are the teratogenic effects of vit A and What test must be ordered before starting a woman on isotreitinoin for severe acne
UGA - UAA and UAG
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Liver hepatocytes and steroid producing cells of the adrenal cortex
Cleft palate - cardiac abnl - pregs test

20. What amino acid makes up most of the octamer
Lysine and arginine
Abnormal protein folding - degradation before reaching cell surface
Stored ATP - creatine phosphate - anaerobic glycolysis
SNP

21. nucleotide repeat for fredreich's ataxia
Mutated dystrophin gene - less severe - adolescence
Acetyl - CoA carboxylase (ACC)
GAA
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

22. What is NADPH used for
Medial dorsal nucleus of thalamus - mamillary bodies
Anabolic processes as a supply of reducing equivalents
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Terminal regions - tropocollagen

23. Infection with what organism can cause B12 def
Diphyllobothrium latum
Uses ATP to add high energy phophate group onto substrate
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
HMG- CoA (HMG- CoA to mevalonate

24. What co - factors are required for the pyruvated dehydrogenase complex
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
IMP precursor
Covalent cross - linking by lysyl oxidase to make collagen fibrils

25. What is the RDE of TCA cycle
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Isocitrate dehydrogenase
More than 1 codon may code for the same amino acid

26. How does insulin inhibit glycogenolysis
Ca/calmodulin in muscle to coordinate with muscle activity
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible

27. What causes Edwards syndrome and What is it
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
9+2 arrangement of microtubules
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Neuralgia

28. What does a southern blot use as its sample
Von gierkes - glucose 6 phosphatase
DNA
9+2 arrangement of microtubules
Anabolic processes as a supply of reducing equivalents

29. What collagen type is most frequently affected in ehlers danlos and What are common complications
III - joint dislocation - anuerysms - organ rupture
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Leu - lys
Collagen

30. What part of the pre mRNA contains the actual genetic information coding for protein
Malonyl coa
Carbomoyl phosphate synthetase I
Exons
N to C

31. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
Binds 50S - blocking translocation
32 - malate aspartate shuttle
PCR - denaturation - annealing - elongation
Catabolic processes to carry reducing equivalents away as NADH

32. In which single strand DNA repair mechanism do specific endonucleases release the oligonucTIDE containing bases and DNA poly and ligase fill and reseal - and what disease occures when this is mutated
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Met - val - arg his
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

33. What can vit B3 be used to treat
Histidine
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
EtOH dehydrogenase and acetaldehyde dehydrogenase
Hyperlipidemia

34. In which direction is protein synthesized
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Proline and glycine (non glycosylated forms)
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
N to C

35. What is heteroplasmy
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Skin
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

36. What converts tyrosine to DOPA
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Tryosine hydroxylase
Grows slowly - collapses quickly
Oxidative is irreversible

37. How do tetracyclines work
Biotin
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Alpha and beta tubulin - dimers have two GTP bound
Exercise: inc NAD/NADH - inc ADP - inc Ca

38. protein malnutrition resulting in skin lesions - edema and liver malfxn
Kwashiorkor - small child with swollen belly
40 - 60 - 80
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible

39. What regulates whether FBPase -2 or PFK-2 is active
Protein kinase A
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
MRNA
High output cardiac failure - dilated cardiomyopathy - edema

40. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Inc CPK and muscle biopsy
FAP
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Basement membrane or basal lamina

41. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Karyotyping
Type II
O- oligosaccharaides
SnRNPs

42. What is the activated carrier for 1 carbon units
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
THFs
Inhibits the Na/K pump by binding the K side

43. What metabolic rxns occur in the cytoplasm
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Pyruvate to oxaloacetate (3C to 4C)
Carnitine acyltransferase I
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

44. What does lactase deficiency cause
Promotor - TATA box - and CAAT box - AT rich
The triphosphate bond
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Removal of N or C termal propeptides from zymogens to generate mature proteins

45. What is the defect in fructose intolerance and What does it cause
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Muscle
IDL
Anabolic processes as a supply of reducing equivalents

46. What components come together to make S- adenosyl methionine
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Microarrays
ATP and methionine
B12 and folate

47. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Hypoxanthine to xanthing and xanthine to uric acid
30 - glycerol -3- phosphate shuttle
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Binds to LDL receptor - mediates VLDL secretion

48. How is Lesch Neyhan inherited
Unmethylated - newly synthesized - HNPCC
1 -25 OH2 D3 = calcitriol
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
X- linked recessive

49. What is the name is fxn of vit B3
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Niacin - constituent of NAD and NADP - derived from tryptophan
Sucrose = glucose + fructose - lactose = glucose + galactose
Sulfation

50. Which aspect of the spliceosome do patients with lupus make antibodies against
Liver - ovaries - seminal vesicles
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
SnRNPs