Test your basic knowledge |

Biochemistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

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. How many nucTIDEs is a tRNA and What does the secondary sturcture form
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
75 to 90 - cloverleaf
Histidine
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

2. What is disulfiram used for
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Silencers
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
25OHD3

3. What does desmin stain for
Phenytoin - MTX - and sulfonamides
Muscle
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
Mutated dystrophin gene - less severe - adolescence

4. An inability to convert orotic acid to UMP would be caused by a deficiency either of which two enzymes

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

5. Is there any requirement for homology in NHEJ
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Result from phagocytic removal of heinz bodies my macs - G6PD def
Fasting
No - its non homologous

6. What does an umabiguous genetic code refer to...
Colchicine
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Wernicke - korsakoff - dry and wet beriberi
Each codon specifies only 1 amino acid

7. caf
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Mebendazole/thiabendazole
Schilling test
Neurofibromatosis type 1 (von Recklinghausens disease)

8. What metabolic rxns occur in the mitochondria
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Ribose 5- P to PRPP

9. What else can phosphoylate phosphorylase kinase
Carnitine shuttle - acyl - coa from cyto to mito
Wrinkles and acne
Ca/calmodulin in muscle to coordinate with muscle activity
Oxidative is irreversible

10. Of the four possible fates for pyruvate - which one carries amino groups to liver from muscle
Scrutinizes - hydrolyzes the bond
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Alanine
Adds an inorganic phosphate onto substrate without using ATP

11. What induces pyruvate kinase
F16BP
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Binds 50S - blocking translocation

12. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
CTG
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
Removal of N or C termal propeptides from zymogens to generate mature proteins
Krabbes - galactocerebrosidase - galactocerebroside - AR

13. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
17 - 17 letters in von Recklinghausen
Glycogenolysis to form glucose
Karyotyping
Glycogen synthase

14. What kind of RNA is transported out of the nucleus
Activates LCAT
Only processed RNA
40 - 60 - 80
Adds 2 carbon with the help of biotin

15. What does the vimentin stain for
Connective tissue
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
More than 1 codon may code for the same amino acid
Purines= A - G pyrimidine = C - T (U)

16. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Basement membrane or basal lamina
Collagen
Q -
Fibrofatty replacement of muscle - cardiac myopathy

17. What does a phosphatase do
Tyrosine
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Removes phosphate group from substrate
P2 +2pq+ = 1

18. What are uncoupling agents
Familial hypercholesterolemia - hyperlipidemia type IIA
Fasting
Oral uridine administration
Inc permeability of membrane causing a dec in proton gradient and inc in O2 consumption - ATP synthesis stops - but electron transport continues to produce heat

19. What is the RDE of fatty acid oxidation
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Carnitine acyltransferase I
Lysine and arginine
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

20. What ribosomes do prokaryotes have
FMR1 gene - methylation - associated with chromosomal breakage
Neural tube
30 - 50 - 70
Breaks down acyl - coa to acetyl coa groups in mito

21. Where is vit B12 found
Disorder of aromatic amino acid metabolism
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

22. What is the fxn of vit D
Unmethylated - newly synthesized - HNPCC
Phosphorylation - glycosylation - hydroxylation
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty

23. delivers hepatic TGs to peripheral tissue - secreted by liver
VLDL
Met - val - arg his
Glutamine PRPP amidotransferase
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

24. How do tetracyclines work
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Acetoacetate and beta hydroxybutyrate
Alpha 1 -4 glucosidase
Leu - lys

25. What are the results of unbalanced translocation
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

26. What does the CFTR channel do in the lungs - GI tract and skin
Karyotyping
Removal of N or C termal propeptides from zymogens to generate mature proteins
Active secretion in lungs and GI - reabsorbs in skin
X linked frame shif mutation

27. What does apoB48 do
Deamination
CTG
Mediates chylomicron secretion
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

28. What is regeneration of methionine depedent on...
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
B12 and folate
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
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

29. What apolipoproteins are on chylomicrons
B48 - AIV - CII - E
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

30. What are the blood glucose levels maintained by for days 1-3
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)
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Neg to pos
Liver hepatocytes and steroid producing cells of the adrenal cortex

31. What is the most common urea cycle disorder and What is the mode of inheritance?
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females
Post to neg
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Medial dorsal nucleus of thalamus - mamillary bodies

32. What do the single stranded binding proteins do
Prevent strands from reannealing
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Dopa decarboxylase

33. What does CATCH 22 stand for and What causes is...
17 - 17 letters in von Recklinghausen
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
OTC has hyperammonemia - orotic aciduira does not
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

34. What apolipoprotiens are on VLDL
Oral uridine administration
B-100 - CII and E
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

35. Infection with what organism can cause B12 def
Diphyllobothrium latum
Degradation of TG stored in adipocytes
Mediates chylomicron secretion
Dec methionine - inc cystiene - inc B12/folate

36. What is the pathway in the fasting state leading to inc FBPase -2 and dec PFK-2
Inc glucagon - inc cAMP - inc PKA
Oxidative is irreversible
G6PD
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty

37. What is maternal PKU
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Eu - methionine - pro - formyl - methionine
X- linked recessive
Hypoxanthine to xanthing and xanthine to uric acid

38. What does the golgi assemble proteoglycans from
Essential fructosuria - fructokinase AR
Zero
Dopamine beta hydroxylase
Core proteins

39. What fxn does glucokinase serve in the liver
Glycogenolysis to form glucose
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

40. This is the site where negative regulators bind
Met - val - arg his
Malonyl coa
Arginine
Silencers

41. Which bond is stronger AT or CG and why? What is the laboratory consequence of this?
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Stored ATP - creatine phosphate - anaerobic glycolysis
CG- 3 > AT-2 - More CG content - melting point goes up
No - its non homologous

42. What do def in in enzymes of gluconeogenesis cause
Result from phagocytic removal of heinz bodies my macs - G6PD def
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Hypoglycemia
Biotin

43. What substance inside the cell serves to oxidize glutatione
FAP
VMA
Inc dicarboxylic acids - dec in glucose and ketones
Peroxide

44. What are the glucogenic essential amino acids
Catabolic processes to carry reducing equivalents away as NADH
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Met - val - arg his

45. What does the passage of electrons result in that when coupled to OXPHOS drives the production of ATP
3' end (with CCA)
Proton gradient
Removal of N or C termal propeptides from zymogens to generate mature proteins
Essential fructosuria - fructokinase AR

46. What does DNA poly I do?
DNA
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Protective against malaria

47. Which anti breast cancer drugs work on micortubules
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
Paclitaxel
BOne
Glycine - aspartate - glutamine

48. I g fat = ? Kcal
Nine
Locus heterogeneity - ocular albinism is x- linked recessive
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Covalent cross - linking by lysyl oxidase to make collagen fibrils

49. What substance inside the cell reduces glutatione
Basement membrane or basal lamina
NADPH
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

50. What is the function of biotin
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
1 kind with multiple subunits
VLDL
Bone - skin - tendon - dentin - fascia - cornea - late wound repair