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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. 90% of ADPKD cases are due to a mutation In what gene
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Cri du chat
APKD1 on chromosome 16
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

2. What substance inside the cell serves to oxidize glutatione
Result from phagocytic removal of heinz bodies my macs - G6PD def
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Peroxide
ADPKD

3. What clotting factors require vit K
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
P2 +2pq+ = 1
II - VII - IX - X (1972) protein C and S
Site of steroid synthesis and detoxification of drugs and poisons

4. What two amino acids are required druing periods of growth and why
Collagen
Neither of 2 alleles is dominant - blood groups
Arg and his inc in histones Which bind negatively charged DNA
SAM

5. What is the pathway in the fasting state leading to inc FBPase -2 and dec PFK-2
Tryosine hydroxylase
Inc glucagon - inc cAMP - inc PKA
GAA
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

6. What are ketone bodies made from - where are they metabolized and how are they excreted
B6
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Particular sequence of DNA where replicatino begins - may be single of multiple
Inhibits 50S peptidyltransferase

7. What does a mischarge tRNA do
Glycine - aspartate - glutamine
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Liver and leafy veggies
Reads usual codon but inserts wrong AA

8. In what cells do the respiratory burst occur
B100 and E
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
PMNs
B48 - AIV - CII - E

9. How do fluoroquinolones work
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Ile - phe - thr - trp
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

10. What is linkage disequilibrium
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Lacks glucose 6 phophatase
Malonyl coa
Orotic acid to UMP

11. What causes Down syndrome
Neuralgia
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

12. What converts tyrosine to DOPA
AMP - fructose 2 -6 BP
Cri du chat
Tryosine hydroxylase
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

13. What are bite cells and when do you see them
Neither of 2 alleles is dominant - blood groups
Mediates extra remnant take up
Result from phagocytic removal of heinz bodies my macs - G6PD def
Acetly- CoA - CO2 - NADH

14. What substances directly inhibit electron transport chain
Rotenone - CN- - antimycin A - CO
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Inhibits RNA polymerase II - found in death cap mushrooms
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

15. What are the blood glucose levels maintained by for days 1-3
B48 - AIV - CII - E
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
G6PD
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)

16. What enzyme results in classic galactosemia and What is the clinical
Carbomoyl phosphate synthetase I
Cofactor for LPL
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

17. What do B- complex vitamin deficiencies often result in
ATP
Dermatitis - glossitis - and diarrhea
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
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

18. What does the golgi assemble proteoglycans from
Alpha and beta tubulin - dimers have two GTP bound
Core proteins
30 - glycerol -3- phosphate shuttle
Oxidizes substrate

19. What is NADPH's role inside RBCs
Binds 50S - blocking translocation
Elastase - inhibited by alpha1 antitrypsin
Keep glutathione reduced so it can detoxify free radicals and peroxides
Adds 2 carbon with the help of biotin

20. How do odd chain fatty acids participate in gluconeogenesis
Liver - also in kidney and gut epithelium
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Debranching enzyme

21. What is the fxn of vit K
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Von Gierke's - Pompe - Cori - McArdle
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Flagella - cilia - mitotic spindles

22. In a marathon Where does energy come from
Ketone - methyl
Biotin
Glycogen and FFA oxidation; glucose conserved for final sprinting
Cyclin dependent kinases;constitutive and inactive

23. What are the two possible causes of albinism
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Tryptophan
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
X- linked recessive

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
Flank pain - hematuria - HTN - progressive renal failure
Same as sprint + OXPHOS
Chylomicrons
3' end (with CCA)

25. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
Tuberous sclerosis
Glycogen phosphorylase
Protein
Epithelial cells

26. What is the Name and function of vit B2
Nissl body - enzyme and NTs
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Enhancers
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

27. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
HVA
Tryptophan
Promotor - TATA box - and CAAT box - AT rich
CG- 3 > AT-2 - More CG content - melting point goes up

28. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
Krabbes - galactocerebrosidase - galactocerebroside - AR
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Glutamine PRPP amidotransferase
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

29. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Cleft palate - cardiac abnl - pregs test
Sucrose = glucose + fructose - lactose = glucose + galactose
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Terminal regions - tropocollagen

30. Giving folate during early pregnancy is important to prevent what birth defects
Exercise: inc NAD/NADH - inc ADP - inc Ca
Neural tube
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Reads usual codon but inserts wrong AA

31. What does fomepizole do
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
40 - 60 - 80
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Mitochondria

32. Describe the structure of cilia
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Neurons
9+2 arrangement of microtubules
Met - val - arg his

33. congenital microdeletion of short arm of chromosome 5 with microcephaly - moderate to severe mental retardation - high pitched crying/meying - epicanthal folds - cardiac abnl
Defect in fibrillin
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Cri du chat
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

34. What is the activated carrier for Co2
Biotin
Chylomicrons
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Site of steroid synthesis and detoxification of drugs and poisons

35. What are the results of pancreatic insuff in CF
Malabsorption and steatorrhea (ADEK)
GTP
Peroxide
Phosphorylation - glycosylation - hydroxylation

36. What is pleiotropy and given an example
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
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
Arg and his inc in histones Which bind negatively charged DNA
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes

37. Which direction does dynein go
Post to neg
Wernicke - korsakoff - dry and wet beriberi
OTC has hyperammonemia - orotic aciduira does not
Tryosine hydroxylase

38. What is the breakdown product of epi
30 - glycerol -3- phosphate shuttle
Metanephrine
Glycogen phosphorylase
Specific glycosylases - AP endonuclease

39. characterize autosomal domint inheritance
High output cardiac failure - dilated cardiomyopathy - edema
GTP
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

40. What creates the musty body odor in PKU
Hyperlipidemia
Disorder of aromatic amino acid metabolism
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Modifies N- oligosaccharides

41. What is the hardy weinber heterozygote prevalence
2pq
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Carbomoyl phosphate synthetase II
Inc insulin - dec cAMP - dec PKA

42. What does apoCII do
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Cofactor for LPL
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Glutamine PRPP amidotransferase

43. What occurs to oxaloacetate in starvation and DKA
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Disease
Attachment of ubiquitin to defective proteins tag them for breakdown

44. What does Citrate Is Krebs starting substrate for making oxaloacetate
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
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Nonsense > missense > silent
DNA

45. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Glycogen synthase
Oxalacetate
Phosphorylation - glycosylation - hydroxylation

46. What catacholamine step is SAM required for
Orotate precursor - with PRPP added later
Conversion of NE to epi
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
ADPKD

47. What does amino acid catabolsim results in the formation of what?
After citruline
Inc vit B6
Site of steroid synthesis and detoxification of drugs and poisons
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

48. In which structures do you find microtubules
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Ribose 5- P to PRPP
Flagella - cilia - mitotic spindles

49. What kind of RNA is transported out of the nucleus
Supply sufficient glucose to brain and RBCs and to preserve protein
Only processed RNA
Glucose 6 phosphatase
FAP

50. What is the defect in II A familial hypercholesterolemia
Mebendazole/thiabendazole
17 - 17 letters in von Recklinghausen
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
HMG- CoA synthase