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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. Where are cytosolic and organellar proteins made
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
SnRNPs
Free ribosomes
Inhibits the Na/K pump by binding the K side

2. What catacholamine step is SAM required for
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
FMR1 gene - methylation - associated with chromosomal breakage
Conversion of NE to epi
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase

3. What CETP do
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
THFs
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

4. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Mediates chylomicron secretion
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
MEN - 2A and 2B with ret gene
ATP - citrate

5. What is I cell disease
RER
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Glucose - 2Pi - 2ADP - 2NAD+
Cartilage - hyaline - vitreous body - nucleus pulposus

6. What are the findings with homocystinuria and What amino acid is needs to be supplemented
HMP shunt
Mediates extra remnant take up
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Inhibit DNA gyrase specific for prokaryotic topoisomerase

7. Which anticancer drugs work on microtubules
Inhibits RNA polymerase II - found in death cap mushrooms
Vincritsine/vinblastine
Marfans
More than 1 codon may code for the same amino acid

8. What converts dopamine to NE
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Neurons
Dopamine beta hydroxylase
PCR - denaturation - annealing - elongation

9. What are cyclin - CDK complexes
Neuralgia
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Must be both activated and inactivated for cell cycle to progress

10. What is used to diagnose muscular dystrophies
Catabolic processes to carry reducing equivalents away as NADH
Inc CPK and muscle biopsy
Inhibits RNA polymerase II - found in death cap mushrooms
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels

11. What are the 3 AR forms of homocystinuria
BOne
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
2 rings

12. Where is PEP carboxykinase found - What does it do - and What does it require
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
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
Griseofulvin

13. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
ATP and alanine
Enhancers

14. What are the characteristics of angelmans syndrome and How does it occur
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Inc melt - dec fluidity

15. What test is used for B12 def
Schilling test
Type II
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Alkaptonuria - may have debiliating arthralgias

16. What does helicase do
B100 and E
Unwinds DNA template at replcation fork
Uses ATP to add high energy phophate group onto substrate
Glycolysis and aerobic respiration

17. What is anticipation and give an example
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Dopamine beta hydroxylase
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons

18. What else can phosphoylate phosphorylase kinase
Ca/calmodulin in muscle to coordinate with muscle activity
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
FMR1 gene - methylation - associated with chromosomal breakage
Palate - facial and cardiac defects

19. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
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
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes

20. Which anti gout drugs work on microtubules
Colchicine
Dopamine beta hydroxylase
Males are infertile due to bilateral absence of vas deferens
UDP glucose pyrophosphorylase

21. What is mosaicism and give an example
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
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
Fibrofatty replacement of muscle - cardiac myopathy
HDL

22. What does the primary transcript combine with to form the spliceosome
PFK - rate limiting enzyme
SnRNPs and other proteins
NADH - NADPH - FADH2
Inc dicarboxylic acids - dec in glucose and ketones

23. What is the RDE of the HMP shunt
Proline and glycine (non glycosylated forms)
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Glucose 6 phosphate dehydrogenase (G6PD)
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

24. What tissues have both enzymes of sorbitol metabolism
Alpha 1 -6 and alpha 1 -4
Liver - ovaries - seminal vesicles
DNA
Terminal regions - tropocollagen

25. Milder form of type I with nl blood lactate levels - dz and enzyme

26. What converts DOPA to dopamine
Rb and p53
Dopa decarboxylase
Wobble
17 - 17 letters in von Recklinghausen

27. 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
ADPKD
Intermediate filaments
5' of the incoming nucleotide

28. deletion of VHL gene on chromosome 3 leading to hemangioblastomas of retina/cerebellum/medulla bilateral RCC - dz and overexpression product
Makes RNA primer on which DNA poly III can initiate replication
Von hippel lindau - 3
After day 1
PMNs

29. What are the fetal screening measures for Down
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
N to C
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

30. What is the fxn of vit K
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
ATP
ATP - citrate
Connective tissue

31. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Autosomal recessive diseases
Specific glycosylases - AP endonuclease
RRNA

32. What does arsenic do and What are th results of poisoning
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Grows slowly - collapses quickly
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

33. What is the RDE of de novo pyrimidine synthesis
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Carbomoyl phosphate synthetase II
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

34. Which step in the de novo purine and pyrimidine synthesis pathway requires aspartate - glycine - glutamine and THF
Infection - free radicals generated by inflammatory response
F16BP
Ribose 5- P to PRPP
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

35. What happens with wet beriberi
African Americans and Asians
High output cardiac failure - dilated cardiomyopathy - edema
Collagen
After day 1

36. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Ketone - methyl
Inhibits 50S peptidyltransferase
Procollagen - triple helix of 3 alpha collagen chains
FAP

37. What does desmin stain for
Neural tube
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Muscle
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

38. What happens on the oxidative arm of the HMP shunt and What is the key enzyme
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Neg to pos
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

39. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Acetoacetate and beta hydroxybutyrate
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Huntingtons
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

40. How is vit D stored
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Two
25OHD3
Particular sequence of DNA where replicatino begins - may be single of multiple

41. Where is hexokinase found - What is its Km and Vmax and what uninduces it
Mutated dystrophin gene - less severe - adolescence
Lariat shape in order and remove intron precisely and join 2 exons
Palate - facial and cardiac defects
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin

42. What is the function of biotin
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Creat a nick in the helix to relieave supercoils created during replication
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Inc intestinal absorption fo calcium and phosphate - inc bone resorption

43. What neuroanatomical strutures are injured in wernicke - korsakoff
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Medial dorsal nucleus of thalamus - mamillary bodies
FAP
B48 - AIV - CII - E

44. What induces pyruvate kinase
F16BP
Enhancers
Phenylalanine hydroxylase
II - VII - IX - X (1972) protein C and S

45. What are purines made from
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
IMP precursor
Base + ribose

46. What reaction does adenosine deaminase normally catalyze
Malapsorption syndromes like sprue or CF or mineral oil intake
Inhibits RNA polymerase II - found in death cap mushrooms
ATP
Adenosine to inosine

47. What enzyme results in classic galactosemia and What is the clinical
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Each codon specifies only 1 amino acid
Alanine
Adds 2 carbon with the help of biotin

48. What 3 steps in RNA processing occur after transcription

49. Which end of the tRNA is the amino acid bound to...

50. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Neg to pos
Liver and leafy veggies
CFTR gene - 7 - Phe 508
Unwinds DNA template at replcation fork