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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. What is proteasomal degredation
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Attachment of ubiquitin to defective proteins tag them for breakdown
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

2. Where is EtOH dehydrogenase located
Diphyllobothrium latum
Nine
Cytosol
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

3. What are the characteristics of angelmans syndrome and How does it occur
Citrate - acetyl coa from mito to cyto
Purines= A - G pyrimidine = C - T (U)
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

4. What does universal genetic code refer to and What are some exception
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Malapsorption syndromes like sprue or CF or mineral oil intake
Myeloperoxidase
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

5. Do balanced translocations cause abnl phenotype
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Liver and leafy veggies
No
Read from a fixed starting point as a continuous sequence of bases

6. Which anticancer drugs work on microtubules
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Vincritsine/vinblastine
Binds to LDL receptor - mediates VLDL secretion
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

7. What metabolic rxns occur in both the cytoplasm and mitochondria
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

8. How do microtubules grow and collapse
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Kwashiorkor - small child with swollen belly
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Grows slowly - collapses quickly

9. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
PCR - denaturation - annealing - elongation
Oxidative and nonoxidative - no ATP produced or used
PMNs
Intermediate filaments

10. What are the symptoms of vit A def
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Night blindness - dry skin
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Comlex II

11. What is used to diagnose muscular dystrophies
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Asp and Glu
Inc CPK and muscle biopsy
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

12. What happens in vit K def
B100 and E
CarTWOlage
Proline and lysine - vit C
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx

13. What inhibits pyruvate kinase
Abnormal protein folding - degradation before reaching cell surface
ATP and alanine
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Inc insulin - dec cAMP - dec PKA

14. nucleotide repeat for fredreich's ataxia
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
GAA
Von Gierke's - Pompe - Cori - McArdle
Ribos first then deoxyribos with ribonucleotide reductase

15. What is the defect in fructose intolerance and What does it cause
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Biotin

16. What is locus heterogeneity and give an example
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
5' of the incoming nucleotide
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Transfers methyl units

17. What is disulfiram used for
Liver and leafy veggies
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Specific glycosylases - AP endonuclease
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase

18. What is the result of vit B5 def
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Inhibits 50S peptidyltransferase
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

19. What enzyme def can cause emphysema
Creat a nick in the helix to relieave supercoils created during replication
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Alpha1 antitrypsin
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

20. What are ketone bodies made from - where are they metabolized and how are they excreted
P2 +2pq+ = 1
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
1 kind with multiple subunits

21. Why can't muscle produce in gluconeogenesis
Ca/calmodulin in muscle to coordinate with muscle activity
Lacks glucose 6 phophatase
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx

22. When does aspartate enter the urea cycle
Nonsense > missense > silent
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
After citruline
Inc melt - dec fluidity

23. How is Lesch Neyhan inherited
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
CGG
Zero
X- linked recessive

24. What does the golgi assemble proteoglycans from
Palate - facial and cardiac defects
Core proteins
Williams syndrome
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

25. what gene is implicated in fragile X syndrome - and What is the mutation
P2 +2pq+ = 1
FMR1 gene - methylation - associated with chromosomal breakage
Lysine and leucine
Thymic - parathyroid and cardiac

26. In prokaryotes - What does makes the different types of RNA
Inhibits RNA polymerase II - found in death cap mushrooms
Particular sequence of DNA where replicatino begins - may be single of multiple
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
1 kind with multiple subunits

27. What is the activated carrier for electrons
Cytosol
NADH - NADPH - FADH2
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Pseudomonas and s aureus

28. What does the vimentin stain for
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Connective tissue
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

29. What is the energy source after day 3 of starvation
Wernicke - korsakoff - dry and wet beriberi
2 rings
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
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

30. Which amino acids are elastin rich in
Proline and glycine (non glycosylated forms)
AMP - fructose 2 -6 BP
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Must be both activated and inactivated for cell cycle to progress

31. What is the active form of vit D
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
9+2 arrangement of microtubules
Mcardle's - skeletal muscle glycogen posphorylase
1 -25 OH2 D3 = calcitriol

32. What enzyme esterifies 2/3 of plasma cholesterol
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
LCAT (lecithin cholesterol acyltransferase)
Must be both activated and inactivated for cell cycle to progress
CAG - 4

33. What is dominant negative mutation and give an example
Sulfation
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding
NAD+

34. What does the golgi add to serine and threonine residues
O- oligosaccharaides
Cleft palate - cardiac abnl - pregs test
Comlex II
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

35. What does hepatic TG lipase do
X linked frame shif mutation
Degradation of TG remaining in IDL
FAP
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

36. What does a kinase do
Mental retardation - flat facies - prominent epicanthal folds - simian crease - gap between 1st 2 toes - duodenal atresia - congenital heart disease (ASD) - inc risk of All and Alzheimers
Uses ATP to add high energy phophate group onto substrate
Dec DNA - dec lymphos leads to SCID
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins

37. What is the amino acid precursor for porphyrin and heme
Mediates extra remnant take up
Kidney - ears - eyes
Glycine
No

38. Type II collagen
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Cartilage - hyaline - vitreous body - nucleus pulposus

39. What causes maple syrup urine disease and What does it lead to...
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
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
40 - 60 - 80
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

40. central and peripheral demyelination with ataxia and dementia
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Degradation of TG stored in adipocytes
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

41. Describe the replication fork
HMG- CoA (HMG- CoA to mevalonate
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Supply sufficient glucose to brain and RBCs and to preserve protein

42. What is the pathway in the fed state leading to dec FBPase -2 and inc PFK-2
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Core proteins
Inc insulin - dec cAMP - dec PKA
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding

43. What is the activated carrier for Acyl
Rotenone - CN- - antimycin A - CO
More than 1 codon may code for the same amino acid
Coenzyme A - lipoamide
HMG- CoA reductase

44. What test is used for B12 def
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Schilling test
Prevent strands from reannealing
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

45. What is the defect in II A familial hypercholesterolemia
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Lysine and leucine
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol

46. How many ATP are produced by anearobic glycolysis per molecule of glucose
Metanephrine
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Two
Microtubules

47. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Vincritsine/vinblastine
After citruline
Must be both activated and inactivated for cell cycle to progress
Hereditary spherocytosis

48. Type I bone
Glucose - 2Pi - 2ADP - 2NAD+
TTP
Microtubules
BOne

49. What does GFAP stain for
Neuralgia
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Hereditary spherocytosis

50. What apolipoproteins are on IDL
30 - 50 - 70
30 - glycerol -3- phosphate shuttle
Myeloperoxidase
B100 and E