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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. In what cells do the respiratory burst occur
PMNs
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Binds 50S - blocking translocation
Bind 30s subunit preventing attachment of aminoacyl - tRNA

2. characterize autosomal domint inheritance
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Cartilage - hyaline - vitreous body - nucleus pulposus
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Pyruvate - NAD+ - CoA

3. Which antifungal drugs work on microtubules
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
Griseofulvin
Fed
Glucose - 2Pi - 2ADP - 2NAD+

4. What are the findings in PKU
AMP - fructose 2 -6 BP
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

5. In mismatch repair - which strand is recognized and In what hereditary syndrome is this defective
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Unmethylated - newly synthesized - HNPCC
Met - val - arg his
Dermatitis - enteritis - alopecia - adrenal insuff

6. What causes Hartnup's disease
FAP
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year

7. what gene is implicated in fragile X syndrome - and What is the mutation
1 ring
They yield only acetyl - CoA equivalents
FMR1 gene - methylation - associated with chromosomal breakage
VLDL

8. What are the characteristics of angelmans syndrome and How does it occur
Degredation of dietary TG in small intestine
Propionyl - CoA to methylmalonyl - CoA (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
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

9. Describe the location and fxn of the Na/K ATPase
1 ring
FISH
Anabolic processes as a supply of reducing equivalents
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side

10. What are the 3 AR forms of homocystinuria
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

11. What are the characteristics of prader willi syndrome How does it occur
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Specific glycosylases - AP endonuclease
RNA poly II
Glucose - 2Pi - 2ADP - 2NAD+

12. Where is glucokinase found - What are the Km and Vmax - and what induces it
Free ribosomes
Stop codon is recognized by release factor - and completed protein is released from ribosome
Glycine
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

13. Which are the basic amino acids
Paclitaxel
Arg - lys - his - arg is most basic - has has no charge at body pH
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
APKD1 on chromosome 16

14. What is trimming
Removal of N or C termal propeptides from zymogens to generate mature proteins
APRT + PRPP
Euchromatin
Foliage - small reserve in liver - eat green leaves

15. What activates the pyruvate dehydrogenase complex
25OHD3
Exercise: inc NAD/NADH - inc ADP - inc Ca
TTP
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins

16. Infection with what organism can cause B12 def
Diphyllobothrium latum
Fasting
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Mebendazole/thiabendazole

17. What ribosomes do prokaryotes have
30 - 50 - 70
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
LCAT (lecithin cholesterol acyltransferase)

18. What can vit B3 be used to treat
P+q = 1
Hyperlipidemia
SnRNPs
Base + ribose

19. What is the rate determining enzyme (RDE) of glycolysis
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
Phosphofructokinase 1
Glucose 6 phosphate dehydrogenase (G6PD)
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

20. What are the priorities for the body in fasting and starvation
Supply sufficient glucose to brain and RBCs and to preserve protein
Nonsense > missense > silent
ADPKD
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms

21. If two alleles are present - but the active allele is deleted - what happens
Disease
Failure to track objects or develop a social smile
Achondroplasia
Tryosine hydroxylase

22. What does NADPH oxidase deficiency result in and why
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Inhibits 50S peptidyltransferase
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

23. What causes Marfan syndrome
Inhibits 50S peptidyltransferase
Free ribosomes
Glucose -6 phosphate
Defect in fibrillin

24. What apolipoproteins are on chylomicrons
Lacks glucose 6 phophatase
B48 - AIV - CII - E
Facial flushing
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora

25. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Terminal regions - tropocollagen
FAP
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Scrutinizes - hydrolyzes the bond

26. What is incomplete penetrence and give an example
Not all individuals with a mutant genotype show the mutant phenotype
African Americans and Asians
Consesus sequenec of base pairs
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

27. Gene imprinting implies that How many alleles are active at a single locus
One
Consesus sequenec of base pairs
Oxidized hemoglobin precipiated within RBCs
B-100 - CII and E

28. 1 g of protein or cabrohydrate = ?kcal
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Four
Collagen
Carbomoyl phosphate synthetase I

29. What happens at the smooth ER
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Makes RNA primer on which DNA poly III can initiate replication
Site of steroid synthesis and detoxification of drugs and poisons

30. Where is vit A found in the diet
Hypoxanthine to xanthing and xanthine to uric acid
Degradation of TG stored in adipocytes
Liver and leafy veggies
Griseofulvin

31. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Targets the proteins for lysosome
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

32. What is the smallest mutation a mircoarray can detect
SNP
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

33. What is the trinucleotide repeat in fragile X
CGG
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Alanine
F16BP

34. What are the 4 assumption of the Hardy Weinberg law
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Neuralgia
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
ATP - citrate

35. How do macrolides and clindamycin work
Binds 50S - blocking translocation
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Myeloperoxidase
Neimann - pick - sphingomyelinase - sphingomyelin - AR

36. When does aspartate enter the urea cycle
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
After citruline
III - joint dislocation - anuerysms - organ rupture

37. What is the RDE of glycogenolysis
75 to 90 - cloverleaf
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Inhibits 50S peptidyltransferase
Glycogen phosphorylase

38. What happens in the first stage of collagen synthesis - and Where does it happen
Lactate
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Metanephrine
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus

39. What is the RDE of fatty acid oxidation
FMR1 gene - methylation - associated with chromosomal breakage
Carnitine acyltransferase I
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Inc intestinal absorption fo calcium and phosphate - inc bone resorption

40. What reaction does adenosine deaminase normally catalyze
UGA - UAA and UAG
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Adenosine to inosine

41. What is NADPH's role inside RBCs
3' end (with CCA)
Keep glutathione reduced so it can detoxify free radicals and peroxides
Malonyl coa
Dermatitis - alopecia - enteritis

42. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
L form
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Lactate
Chylomicrons

43. Which RNA poly opens DNA at promotor site
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
RNA poly II
Mediates extra remnant take up
Metanephrine

44. What are the purely ketogenic amino acids
Leu - lys
Glycogen synthase
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
High output cardiac failure - dilated cardiomyopathy - edema

45. What happens in vit K def
LCAT (lecithin cholesterol acyltransferase)
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Glucose -6 phosphate
Consesus sequenec of base pairs

46. What initiates protein synthesis
Fibrofatty replacement of muscle - cardiac myopathy
Dec DNA - dec lymphos leads to SCID
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

47. what happens in acyl coa dehyrdogenase def
Alanine
Inc dicarboxylic acids - dec in glucose and ketones
Superoxide dismutase
Alpha 1 -6 and alpha 1 -4

48. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
Protective against malaria
Neimann - pick - sphingomyelinase - sphingomyelin - AR
B48 - AIV - CII - E
Essential fructosuria - fructokinase AR

49. What happens in carnitine def
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
P2 +2pq+ = 1
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Ribos first then deoxyribos with ribonucleotide reductase

50. What enzyme does fructose metabolism bypass to reach glycolysis
Flank pain - hematuria - HTN - progressive renal failure
PFK - rate limiting enzyme
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
DTMP