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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 are the names and sources of the two types of vit D found in nature
Robertsonian translocation and mosaicism
ATP hyrdolysis couple to energetically unfavorable rxns
Inc melt - dec fluidity
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

2. What ribosomes do prokaryotes have
B6
Supply sufficient glucose to brain and RBCs and to preserve protein
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
30 - 50 - 70

3. What happens do glycogen in skeletal muscle during exercise
PMNs
Site of steroid synthesis and detoxification of drugs and poisons
Disorder of aromatic amino acid metabolism
Glycogenolysis to form glucose

4. What does SAM do
Transfers methyl units
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan
Oligomycin
ATP - citrate

5. What is the activated carrier for 1 carbon units
Oligomycin
Each codon specifies only 1 amino acid
Carnitine acyltransferase I
THFs

6. What shuttle is used in fatty acid degredation and What does it move and From where to where
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Carnitine shuttle - acyl - coa from cyto to mito
CAG - 4
Alpha - ketoglutarate dehydrogenase complex

7. What happens to glycogen in the liver
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Neimann - pick - sphingomyelinase - sphingomyelin - AR
2pq

8. How many ATP are produced by anearobic glycolysis per molecule of glucose
Rotenone - CN- - antimycin A - CO
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Two
B12 and folate

9. What does apoE do
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Mediates extra remnant take up
RNA
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus

10. What are the fat soluble vitamins and What does their absorption depend on...
One
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Poly A polymerase - signal is AAUAA

11. What does PURe As Gold and CUT The Py stand for
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Neuralgia
Purines= A - G pyrimidine = C - T (U)

12. What is the TX for hyper ammonemia
UDP glucose pyrophosphorylase
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Proton gradient

13. What does an umabiguous genetic code refer to...
Lysine and arginine
Ribos first then deoxyribos with ribonucleotide reductase
Each codon specifies only 1 amino acid
Fructose 1 -6 bisphosphate

14. What are the glucogenic essential amino acids
Cre - lox system
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Achondroplasia
Met - val - arg his

15. What is the amino acid precuros for niacin and serotonin/melatonin
Tyrosine
APRT + PRPP
Creat a nick in the helix to relieave supercoils created during replication
Tryptophan

16. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Inc glucagon - inc cAMP - inc PKA
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two

17. What two cells are particularly rich in RER
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
RNA poly II
Mucus secreting globlet cells and antibody secreting plasma cells
Accelearted muscle breakdown

18. What is the defect in cystinuria
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
NF2 on chromosome 22

19. What enzyme becomes essential in PKU
Acetoacetate and beta hydroxybutyrate
Particular sequence of DNA where replicatino begins - may be single of multiple
Type II
Tyrosine

20. What is the fxn of vit D
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
B-100 - CII and E
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
No

21. What apolipoprotiens are on VLDL
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
B-100 - CII and E
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

22. What is the Name and fxn of vit B5
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
Zero
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan

23. What is the activated carrier for electrons
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
CFTR gene - 7 - Phe 508
32 - malate aspartate shuttle
NADH - NADPH - FADH2

24. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Marasmus - muscle wasting
Inc Cl - in sweat
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
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

25. What kind of RNA is transported out of the nucleus
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Tropoelastin with fibrillin scafolding
Only processed RNA
Carnitine shuttle - acyl - coa from cyto to mito

26. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Locus heterogeneity - ocular albinism is x- linked recessive
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Neg to pos
Proline and lysine - vit C

27. Which bond is stronger AT or CG and why? What is the laboratory consequence of this?
CG- 3 > AT-2 - More CG content - melting point goes up
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
B6
UGA - UAA and UAG

28. what findings are associated with marfans
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Activates LCAT
Foliage - small reserve in liver - eat green leaves

29. What does inc phenylalanine lead to...
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
Griseofulvin
Fasting
Phenylketones in urine

30. What regulates whether FBPase -2 or PFK-2 is active
Malonyl coa
Protein kinase A
Muscle
Particular sequence of DNA where replicatino begins - may be single of multiple

31. What enzyme converts glucose 1 p to UDP glucose
Schilling test
UDP glucose pyrophosphorylase
Base + ribose + phosphate (3' -5') phosphodiester bond
DsRNA promotes degradation of target mRNA knocking down gene expression

32. trinucleotide repeat fo myotonic dystrophy
Cyclin dependent kinases;constitutive and inactive
CTG
Kwashiorkor - small child with swollen belly
Kidney - ears - eyes

33. What is the active form of vit D
Inc vit B6
1 -25 OH2 D3 = calcitriol
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Four

34. What does Ehlers Danlos cause and why
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Oxidizes substrate
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

35. How do fluoroquinolones work
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Chylomicrons
Inhibit DNA gyrase specific for prokaryotic topoisomerase
CG- 3 > AT-2 - More CG content - melting point goes up

36. How is ATP used by the cell
Glycine - aspartate - glutamine
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
ATP hyrdolysis couple to energetically unfavorable rxns
Neg to pos

37. What is the activated carrier for Co2
Niacin - constituent of NAD and NADP - derived from tryptophan
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Inhibits the Na/K pump by binding the K side
Biotin

38. What are the function of vit C
Neg to pos
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
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
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

39. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Dec DNA - dec lymphos leads to SCID
Fasting
Adds an inorganic phosphate onto substrate without using ATP

40. What is linkage disequilibrium
AR
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

41. What induces pyruvate kinase
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Colchicine
N to C
F16BP

42. Where are FADH2 electrons transferred to...
Locus heterogeneity - ocular albinism is x- linked recessive
Comlex II
Colchicine
Each codon specifies only 1 amino acid

43. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Fibrofatty replacement of muscle - cardiac myopathy
IDL
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

44. 1 g of protein or cabrohydrate = ?kcal
Alpha - ketoglutarate dehydrogenase complex
Inc CPK and muscle biopsy
Four
Fed

45. What happens with wet beriberi
Particular sequence of DNA where replicatino begins - may be single of multiple
RNA
HMG- CoA reductase
High output cardiac failure - dilated cardiomyopathy - edema

46. congenital deficiency of homogentisic acid oxidase in the degradative pathway of tyrosine to fumarate leading to dark connective tissue - brown pigmented sclera - urine turns black on standing - dz and worst complication
Cre - lox system
Alkaptonuria - may have debiliating arthralgias
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Medial dorsal nucleus of thalamus - mamillary bodies

47. What enzyme adds Cl - to the H202 to makes bleach
Cytosol
Myeloperoxidase
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Cre - lox system

48. How does insulin inhibit glycogenolysis
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Cyclin dependent kinases;constitutive and inactive
Chylomicrons
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

49. What two amino acids are required druing periods of growth and why
Glucose 6 phosphatase
Arg and his inc in histones Which bind negatively charged DNA
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Tryptophan

50. What is heteroplasmy
Uses ATP to add high energy phophate group onto substrate
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination