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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 two enzymes are involved in EtOH metabolism
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
3' end (with CCA)
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
EtOH dehydrogenase and acetaldehyde dehydrogenase

2. What is the breakdown product of dopamine
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
TTP
HVA
Mcardle's - skeletal muscle glycogen posphorylase

3. What are the fetal screening measures for Down
APC on chromosome 5
Oligomycin
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Active secretion in lungs and GI - reabsorbs in skin

4. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
Elastase - inhibited by alpha1 antitrypsin
Evident in first few days of life - can present last onest - excess carbamoyl phosphate converted to orotic acid - orotic acid in blood and urine - dec BUN and symptoms of hyerpammonemia
Tuberous sclerosis
Neuralgia

5. Where is vit B12 found
Acetyl - CoA
Core proteins
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Karyotyping

6. pyruvate carboxylase catalyzes what rxn
FISH
Oxidizes substrate
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Pyruvate to oxaloacetate (3C to 4C)

7. What is the amino acid precursor for catecholamines
Phenylalanine
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
Disorder of aromatic amino acid metabolism
B-100 - CII and E

8. What are the two possible causes of albinism
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
After day 1
Liver and leafy veggies

9. What does apoCII do
Cofactor for LPL
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
LCAT (lecithin cholesterol acyltransferase)
Debranching enzyme

10. How do fluoroquinolones work
Purines= A - G pyrimidine = C - T (U)
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Lysine and arginine

11. What catacholamine step is SAM required for
Conversion of NE to epi
Site of steroid synthesis and detoxification of drugs and poisons
Dopamine beta hydroxylase
Asp and Glu

12. What does Citrate Is Krebs starting substrate for making oxaloacetate
Same AA - often base change in 3rd position of codon (tRNA wobble)
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Von hippel lindau - 3

13. What is the pathway in the fed state leading to dec FBPase -2 and inc PFK-2
Flank pain - hematuria - HTN - progressive renal failure
Inc insulin - dec cAMP - dec PKA
2 rings
Degredation of TG circulating in chylomicrons and VLDLs

14. What is the breakdown product of NE
Reads usual codon but inserts wrong AA
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Marasmus - muscle wasting
VMA

15. What is the trinucleotide repeat in fragile X
CGG
ATP and methionine
Fibroblast
Stored ATP - creatine phosphate - anaerobic glycolysis

16. characterize x linked dominant
Wobble
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
HVA

17. characterize x linked recessive
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
Q -
Oligomycin
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

18. What are CDKs
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Transfers methyl units
Cyclin dependent kinases;constitutive and inactive
OTC has hyperammonemia - orotic aciduira does not

19. What is the RDE of de novo purine synthesis
Alpha 1 -6 and alpha 1 -4
Glutamate
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Glutamine PRPP amidotransferase

20. What are ketone bodies made from - where are they metabolized and how are they excreted
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
CAG
The triphosphate bond
Initiate chains

21. Where are cytosolic and organellar proteins made
Avidin
Free ribosomes
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Foliage - small reserve in liver - eat green leaves

22. Is there any requirement for homology in NHEJ
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
Griseofulvin
No - its non homologous
Foliage - small reserve in liver - eat green leaves

23. What is the function of folic acid
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Degredation of dietary TG in small intestine

24. What ribosomes do prokaryotes have
30 - 50 - 70
Glucose -6 phosphate
Night blindness - dry skin
Tropoelastin with fibrillin scafolding

25. What is the RDE of TCA cycle
30 - glycerol -3- phosphate shuttle
2 rings
Isocitrate dehydrogenase
Mebendazole/thiabendazole

26. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Free ribosomes
Neurons

27. What are purines made from
Initiate chains
IMP precursor
RNA
Read from a fixed starting point as a continuous sequence of bases

28. recurrent pulmonary infxns in CF are due to what organisms
Alpha 1 -6 and alpha 1 -4
Flagella - cilia - mitotic spindles
Tryosine hydroxylase
Pseudomonas and s aureus

29. What is the result of vit B5 def
Deamination
Dermatitis - enteritis - alopecia - adrenal insuff
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Vincritsine/vinblastine

30. What happens with dry beriberi
Hypoglycemia
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Polyneuritis - symmetrical muscle wasting
Facial flushing

31. in a 100 meter sprint Where does energy come from
Autosomal recessive diseases
Stored ATP - creatine phosphate - anaerobic glycolysis
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Schilling test

32. What are the functinos of vitamin A
Fructose 1 -6 bisphosphate
Glycogen phosphorylase
Citrate - acetyl coa from mito to cyto
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

33. In what cell is collagen synthesis initiated
Oxidized hemoglobin precipiated within RBCs
HMP shunt
Marfans
Fibroblast

34. What defects characterize velocardiofacial syndrome
Schwann cells - lens - retina - kidneys
Palate - facial and cardiac defects
Acetly- CoA - CO2 - NADH
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

35. Type IV collagen is an important structural componenet of the BM for which 3 organs
Kidney - ears - eyes
Acetly- CoA - CO2 - NADH
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
Oxidized hemoglobin precipiated within RBCs

36. What enzyme turns ROS to H2O2
G6PD
Proline and lysine - vit C
Superoxide dismutase
Type II

37. What happens in hyperammonemia
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)

38. What is the RDE of cholesterol synthesis
Alpha 1 -6 and alpha 1 -4
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
HMG- CoA reductase
30 - 50 - 70

39. What does apoB100 do
Glucose 6 phosphate dehydrogenase (G6PD)
Binds to LDL receptor - mediates VLDL secretion
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

40. What bone disorder has x linked dominant inheritance
Failure to track objects or develop a social smile
Phenylethamolamine N methyl transferase
Chylomicrons
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

41. What does Alports syndrome cause and why
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Inhibits 50S peptidyltransferase
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

42. What polar group does guanine have - and what non polar group does thymine have
Ketone - methyl
Carnitine acyltransferase I
Flank pain - hematuria - HTN - progressive renal failure
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

43. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Autosomal recessive diseases
Glycogen and FFA oxidation; glucose conserved for final sprinting
Uses ATP to add high energy phophate group onto substrate

44. What rxn creates ATP
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Dec methionine - inc cystiene - inc B12/folate
Adds 2 carbon with the help of biotin
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

45. What enzyme converts phenylalanine to tyrosin
Phenylalanine hydroxylase
III - joint dislocation - anuerysms - organ rupture
Carnitine shuttle - acyl - coa from cyto to mito
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR

46. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Proline and lysine - vit C
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Glycine - aspartate - glutamine

47. What shuttle is used in fatty acid degredation and What does it move and From where to where
Carnitine shuttle - acyl - coa from cyto to mito
Elastase - inhibited by alpha1 antitrypsin
Promotor - TATA box - and CAAT box - AT rich
Familial hypercholesterolemia - hyperlipidemia type IIA

48. What is the energy source for tRNA actication (charging)
Asp and Glu
ATP
Alpha1 antitrypsin
Colchicine

49. What is the result of vit B5 def
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
African Americans and Asians
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

50. 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
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Dermatitis - glossitis - and diarrhea
30 - glycerol -3- phosphate shuttle
Alkaptonuria - may have debiliating arthralgias