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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. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Result from phagocytic removal of heinz bodies my macs - G6PD def
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

2. What is the activated carrier for Acyl
Coenzyme A - lipoamide
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

3. what disease can cause pellagra
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
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
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Liver - ovaries - seminal vesicles

4. NADPH are used In what 4 things
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
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
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
B-100 - CII and E

5. characterize autosomal recessive inheritance
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Flagella - cilia - mitotic spindles
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
Glycine - aspartate - glutamine

6. What reaction does adenosine deaminase normally catalyze
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
30 - glycerol -3- phosphate shuttle
Adenosine to inosine
Coenzyme A - lipoamide

7. peripheral neuropathy of hands/feet - angiokeratomas - CV/renal disease - dz - def enzyme - acc substrate - inherit
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Fed
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Met - val - arg his

8. What does the addition of mannose -6 phosphate do
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Targets the proteins for lysosome
Autosomal recessive diseases
GTP

9. What is the Name and function of vit B1
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
2 rings
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Post to neg

10. Where are FADH2 electrons transferred to...
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Comlex II
OTC has hyperammonemia - orotic aciduira does not
Wernicke - korsakoff - dry and wet beriberi

11. What does a northern blot use as its sample
SAM
Ca/calmodulin in muscle to coordinate with muscle activity
RNA
In ER - glucose 6- P to glucose

12. What does Ehlers Danlos cause and why
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Ketone - methyl
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US

13. What does CATCH 22 stand for and What causes is...
Nissl body - enzyme and NTs
Robertsonian translocation and mosaicism
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def

14. What does glycosylation of pro alpha chian yield and What is the structure
Procollagen - triple helix of 3 alpha collagen chains
Glucose -6 phosphate
2 -4 DNP - aspirin
VMA

15. What is the RDE of TCA cycle
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Terminal regions - tropocollagen
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Isocitrate dehydrogenase

16. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Karyotyping
Eu - methionine - pro - formyl - methionine
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP

17. What are the two transgenic strategies in mice
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Orotate precursor - with PRPP added later

18. What does a western blot use for its sample
Cyclin dependent kinases;constitutive and inactive
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
NADH - NADPH - FADH2
Protein

19. This is the site where negative regulators bind
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Silencers
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

20. What does the passage of electrons result in that when coupled to OXPHOS drives the production of ATP
Proton gradient
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Comlex II

21. What does commaless - nonoverlapping genetic code refer to...
B12 and folate
Grows slowly - collapses quickly
Read from a fixed starting point as a continuous sequence of bases
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

22. What does a phosphorylase do
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Adds an inorganic phosphate onto substrate without using ATP
Dopa decarboxylase
African Americans and Asians

23. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Marfans
Glucose -6 phosphate
Histidine
Tropoelastin with fibrillin scafolding

24. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Chylomicrons
Rotenone - CN- - antimycin A - CO
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
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

25. Describe the location and fxn of the Na/K ATPase
G6PD
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Medial dorsal nucleus of thalamus - mamillary bodies
GTP

26. What is the activated carrier for electrons
Acetyl - CoA
No
NADH - NADPH - FADH2
Hypoxanthine to xanthing and xanthine to uric acid

27. What is the RDE of glycogen synthesis
ATP
L form
Achondroplasia
Glycogen synthase

28. what gene is implicated in fragile X syndrome - and What is the mutation
Neg to pos
FMR1 gene - methylation - associated with chromosomal breakage
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

29. What is the amino acid precursor for porphyrin and heme
Alpha1 antitrypsin
B100 and E
Uses ATP to add high energy phophate group onto substrate
Glycine

30. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
SAM
Unmethylated - newly synthesized - HNPCC

31. What happens to oxaloacetate in alcholism
30 - glycerol -3- phosphate shuttle
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Infection - free radicals generated by inflammatory response

32. 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
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Glucose 6 phosphate dehydrogenase (G6PD)
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Scrutinizes - hydrolyzes the bond

33. What does pancreatic lipase do
Degredation of dietary TG in small intestine
Particular sequence of DNA where replicatino begins - may be single of multiple
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Myeloperoxidase

34. What does lipoprotein lipase do
Degredation of TG circulating in chylomicrons and VLDLs
After citruline
VLDL
APC on chromosome 5

35. What substances are uncouling agents
Tuberous sclerosis
Cofactor for LPL
2 -4 DNP - aspirin
Carbomoyl phosphate synthetase I

36. How do microtubules grow and collapse
Arginine
Sulfation
Mitochondria
Grows slowly - collapses quickly

37. What is the activated carrier for phosphoryl
ATP
Glucose 6 phosphate dehydrogenase (G6PD)
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
Not all individuals with a mutant genotype show the mutant phenotype

38. ADPKD is associated with What additional conditions
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
Protein kinase A
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
Polycystic liver disease - berry aneurysm - mitral valve prolapse

39. What is proteasomal degredation
Attachment of ubiquitin to defective proteins tag them for breakdown
1 ring
Pyruvate to oxaloacetate (3C to 4C)
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

40. Which anti gout drugs work on microtubules
Colchicine
Infection - free radicals generated by inflammatory response
Exons
African Americans and Asians

41. What is the name is fxn of vit B3
Niacin - constituent of NAD and NADP - derived from tryptophan
Lacks glucose 6 phophatase
Comlex II
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

42. What enzyme esterifies 2/3 of plasma cholesterol
LCAT (lecithin cholesterol acyltransferase)
Liver - also in kidney and gut epithelium
Mcardle's - skeletal muscle glycogen posphorylase
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

43. What are pyrimidines made from
Enhancers
Inc melt - dec fluidity
Cleft palate - cardiac abnl - pregs test
Orotate precursor - with PRPP added later

44. What enzyme degrades a small amount of glycogen in lysosomes
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Alpha 1 -4 glucosidase
CGG
Oxalacetate

45. What is chediak higashi
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
75 to 90 - cloverleaf
Tyrosine
DNA

46. How do cardia glycosides work
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)
CGG
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

47. What is the RDE of cholesterol synthesis
APRT + PRPP
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 reductase
Conversion of NE to epi

48. How are the many staggered tropocollagen molecules reinforced
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Covalent cross - linking by lysyl oxidase to make collagen fibrils
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

49. Where is vit B12 found
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Marasmus - muscle wasting
Glycogen synthase
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

50. A small proportion of Down syndrome is due to What two genetic events
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Glycogenolysis to form glucose
P+q = 1
Robertsonian translocation and mosaicism