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Biochemistry

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1. What is the activated carrier for electrons
NADH - NADPH - FADH2
32 - malate aspartate shuttle
Dopa decarboxylase
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

2. what happens in acyl coa dehyrdogenase def
Inc dicarboxylic acids - dec in glucose and ketones
Huntingtons
PMNs
Phenytoin - MTX - and sulfonamides

3. What is the Name and function of vit B1
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Conversion of NE to epi
By inhibiting formation of the initiation complex and cause misreading of mRNA

4. What does a kinase do
Uses ATP to add high energy phophate group onto substrate
Orotate precursor - with PRPP added later
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Abnormal protein folding - degradation before reaching cell surface

5. What does PURe As Gold and CUT The Py stand for
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Purines= A - G pyrimidine = C - T (U)
Post to neg
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

6. What happens to oxaloacetate in alcholism
Oxidative is irreversible
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Ribos first then deoxyribos with ribonucleotide reductase
Prokaryotic only - degrades RNA primer and fills in the gap with DNA

7. What does Citrate Is Krebs starting substrate for making oxaloacetate
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Sulfation
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
2 -4 DNP - aspirin

8. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Carnitine acyltransferase I
Cre - lox system
Oxalacetate
Accelearted muscle breakdown

9. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
Breaks down acyl - coa to acetyl coa groups in mito
2 rings
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles

10. What are the characteristics of prader willi syndrome How does it occur
Result from phagocytic removal of heinz bodies my macs - G6PD def
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Change resulting in early stop codon
Muscle

11. What are the results of unbalanced translocation
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Glucose -6 phosphate
III - joint dislocation - anuerysms - organ rupture
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

12. What ribosomes do eukaryotes have
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Glucose 6 phosphate dehydrogenase (G6PD)
Muscle
40 - 60 - 80

13. What is chediak higashi
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Autosomal recessive diseases
Free ribosomes
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

14. What does cytokeratin stain for
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
Epithelial cells
Lysine and leucine
Disorder of aromatic amino acid metabolism

15. What is trimming
Glucose 6 phosphate dehydrogenase (G6PD)
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Removal of N or C termal propeptides from zymogens to generate mature proteins
Intermediate filaments

16. What two rxns in in glycolysis require ATP
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Superoxide dismutase

17. What does the golgi apparatus do on asparagine
Microtubules
Modifies N- oligosaccharides
NADPH
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE

18. What is the RDE of TCA cycle
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Disease
Isocitrate dehydrogenase
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE

19. Why does alpha amanitin cause liver failure and Where is it found
RNA
Inhibits RNA polymerase II - found in death cap mushrooms
Makes RNA primer on which DNA poly III can initiate replication
Abnormal protein folding - degradation before reaching cell surface

20. What are the products for glycolysis
Conversion of NE to epi
DsRNA promotes degradation of target mRNA knocking down gene expression
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Scrutinizes - hydrolyzes the bond

21. What is pleiotropy and given an example
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
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
X- linked recessive
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

22. What chromosome is the NF gene on...
Grows slowly - collapses quickly
G6PD
Neurons
17 - 17 letters in von Recklinghausen

23. What is the source of energy in the fasting state between meals
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Ribos first then deoxyribos with ribonucleotide reductase
Orotate precursor - with PRPP added later
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway

24. RNA poly can't proofread - but What can it do
Initiate chains
Alpha 1 -4 glucosidase
Phenytoin - MTX - and sulfonamides
Alkaptonuria - may have debiliating arthralgias

25. nucleotide repeat for fragile x
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Mitochondria
CGG
HMG- CoA reductase

26. Why can't even chain fatty acids produce new glucose
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
9+2 arrangement of microtubules
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
They yield only acetyl - CoA equivalents

27. What occurs to oxaloacetate in starvation and DKA
Blood - bone marrown - amniotic fluid - placental tissue
Met - val - arg his
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
APKD1 on chromosome 16

28. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Paclitaxel
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
G6PD
Actin and myosin

29. What is the trinucleotide repeat in fragile X
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
CGG
Alpha and beta tubulin - dimers have two GTP bound

30. What are the reactants for glycolysis
Inc melt - dec fluidity
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Glucose - 2Pi - 2ADP - 2NAD+
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

31. What substances inhibit phosphofructokinase -1
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Wrinkles and acne
UGA - UAA and UAG
ATP - citrate

32. How do odd chain fatty acids participate in gluconeogenesis
B-100 - CII and E
Autosomal recessive diseases
SNP
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

33. Type IV collagen
Must be both activated and inactivated for cell cycle to progress
Basement membrane or basal lamina
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
P2 +2pq+ = 1

34. What co - factors are required for the pyruvated dehydrogenase complex
Asp and Glu
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

35. Where is glucose 6 phosphatase found and What does it do
Pyruvate - NAD+ - CoA
9+2 arrangement of microtubules
In ER - glucose 6- P to glucose
FMR1 gene - methylation - associated with chromosomal breakage

36. What does SAM do
Transfers methyl units
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Alkaptonuria - may have debiliating arthralgias
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

37. What is loss of heterozygosity and give an example
G6PD
Mebendazole/thiabendazole
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

38. What is RNAi used for
Fed
Marfans
DsRNA promotes degradation of target mRNA knocking down gene expression
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation

39. What is the purpose of the HMP shunt
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
III - joint dislocation - anuerysms - organ rupture
Pyruvate - NAD+ - CoA
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

40. What is the pathway in the fasting state leading to inc FBPase -2 and dec PFK-2
Mitochondria
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Alkaptonuria - may have debiliating arthralgias
Inc glucagon - inc cAMP - inc PKA

41. What are the purely ketogenic amino acids
Glycolysis and aerobic respiration
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Leu - lys
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

42. What is the function of biotin
APC on chromosome 5
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Cyclin dependent kinases;constitutive and inactive
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase

43. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
HGPRT - defective purine salvage - excess uric acid production
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

44. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
African Americans and Asians
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

45. nucleotide repeat for fredreich's ataxia
Krabbes - galactocerebrosidase - galactocerebroside - AR
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
GAA
GTP

46. What does the TCA cycle produce per 1 acetyl CoA
Alpha 1 -4 glucosidase
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

47. What does fomepizole do
Lariat shape in order and remove intron precisely and join 2 exons
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
II - VII - IX - X (1972) protein C and S
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

48. bilateral acoustic schwannomas - juvenile cataracts
Infection - free radicals generated by inflammatory response
NF2 on chromosome 22
Each codon specifies only 1 amino acid
Protective against malaria

49. What causes Down syndrome
Modifies N- oligosaccharides
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes

50. What does Alports syndrome cause and why
Proline and lysine - vit C
32 - malate aspartate shuttle
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora