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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. In a marathon Where does energy come from
Glycogen and FFA oxidation; glucose conserved for final sprinting
Fed
RRNA
Exons

2. What shape does the RNA generate during splicing and why?
Active secretion in lungs and GI - reabsorbs in skin
MRNA - tRNA
Alpha 1 -4 glucosidase
Lariat shape in order and remove intron precisely and join 2 exons

3. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
Core proteins
Base + ribose + phosphate (3' -5') phosphodiester bond
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
Krabbes - galactocerebrosidase - galactocerebroside - AR

4. What does GFAP stain for
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
Debranching enzyme
Neuralgia
Transmitted through both parents - affected mother may have affected children - affected father will have affected children

5. FAP is due to deletion On what gene On what chromosome
Transfers methyl units
APC on chromosome 5
HMG- CoA reductase
Vit K antagonist

6. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Familial hypercholesterolemia - hyperlipidemia type IIA
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Lariat shape in order and remove intron precisely and join 2 exons

7. What does apoCII do
Cofactor for LPL
Four
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Males are infertile due to bilateral absence of vas deferens

8. How do tetracyclines work
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty

9. What does a western blot use for its sample
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
Protein
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
Mucus secreting globlet cells and antibody secreting plasma cells

10. 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
Alkaptonuria - may have debiliating arthralgias
Carnitine shuttle - acyl - coa from cyto to mito
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Nonsense > missense > silent

11. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
Epithelial cells
HGPRT - defective purine salvage - excess uric acid production
Alkaptonuria - may have debiliating arthralgias
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

12. What tissues have only aldose reductase
Disease
Alpha - ketoglutarate dehydrogenase complex
Schwann cells - lens - retina - kidneys
30 - glycerol -3- phosphate shuttle

13. What two enzymes are involved in EtOH metabolism
Essential fructosuria - fructokinase AR
SNP
EtOH dehydrogenase and acetaldehyde dehydrogenase
Carbomoyl phosphate synthetase I

14. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Phosphorylation - glycosylation - hydroxylation
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
75 to 90 - cloverleaf
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

15. What are the complications/signs of familial hypercholesterolemia
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Acetoacetate and beta hydroxybutyrate
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

16. in a 100 meter sprint Where does energy come from
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
9+2 arrangement of microtubules
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Stored ATP - creatine phosphate - anaerobic glycolysis

17. Describe robertsonian translocation
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Acetyl - CoA carboxylase (ACC)
Skin

18. What can excess vit B3 cause
Facial flushing
HMP shunt
Disorder of aromatic amino acid metabolism
VMA

19. In the chromatin structure - which histones form the octamer - and which ties the nucleosome beads together in a string?
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
DTMP
Mitochondria
Robertsonian translocation and mosaicism

20. What is the composition of urea and where do each part derive from
Skin
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility

21. What is a missense mutation
Changed AA (convservative - new AA is similar in chemical structure)
F16BP
4 under the floor
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

22. What do B- complex vitamin deficiencies often result in
Abnormal protein folding - degradation before reaching cell surface
Dermatitis - glossitis - and diarrhea
EtOH dehydrogenase and acetaldehyde dehydrogenase
Euchromatin

23. hepatosplenomegaly - aseptic necrosis of femur - bone crisis - MACS that look like crumpled tissue paper

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24. What enzyme degrades a small amount of glycogen in lysosomes
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Alpha 1 -4 glucosidase
N to C
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses

25. What 3 syndromes are associated with vit B1 def
Wernicke - korsakoff - dry and wet beriberi
4 under the floor
Promotor - TATA box - and CAAT box - AT rich
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

26. What is linkage disequilibrium
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Phenytoin - MTX - and sulfonamides
OTC has hyperammonemia - orotic aciduira does not
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

27. What does commaless - nonoverlapping genetic code refer to...
Assistance of upper extremities to stand up
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Read from a fixed starting point as a continuous sequence of bases
Neurons

28. What can vit B3 be used to treat
Read from a fixed starting point as a continuous sequence of bases
Hyperlipidemia
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Orotic acid to UMP

29. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
30 - glycerol -3- phosphate shuttle

30. What are the clinical features of I cell diesase
Orotate precursor - with PRPP added later
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Mucus secreting globlet cells and antibody secreting plasma cells
Makes RNA primer on which DNA poly III can initiate replication

31. In which state is FBPase -2 active
Glutamine PRPP amidotransferase
EtOH dehydrogenase and acetaldehyde dehydrogenase
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Fasting

32. trinucleotide repeat fo myotonic dystrophy
Intermediate filaments
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
CTG
Creat a nick in the helix to relieave supercoils created during replication

33. What does CATCH 22 stand for and What causes is...
Griseofulvin
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Phenytoin - MTX - and sulfonamides
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

34. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
Thymic - parathyroid and cardiac
DTMP
FISH
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

35. Which enzyme involved in RNA synthesis does not require a template
Neg to pos
No - its non homologous
Colchicine
Poly A polymerase - signal is AAUAA

36. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
LDL
Asp and Glu
Same as sprint + OXPHOS
Degradation of TG remaining in IDL

37. What are the only purely ketogenic amino acids
Protein
Modifies N- oligosaccharides
Lysine and leucine
Carnitine shuttle - acyl - coa from cyto to mito

38. What is variable expression and What is an example
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Nature and severity of phenotype vary from 1 individual to another - NF type 1

39. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Base + ribose
Blood - bone marrown - amniotic fluid - placental tissue
Oral uridine administration
Oxalacetate

40. What does a kinase do
Uses ATP to add high energy phophate group onto substrate
Alpha 1 -6 and alpha 1 -4
Same as sprint + OXPHOS
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

41. What substances inhibit phosphofructokinase -1
Stop codon is recognized by release factor - and completed protein is released from ribosome
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
ATP - citrate
No

42. What does the vimentin stain for
Initiate chains
Dec methionine - inc cystiene - inc B12/folate
Connective tissue
Protective against malaria

43. What does helicase do
Unwinds DNA template at replcation fork
Thymic - parathyroid and cardiac
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate

44. What does acetyl - CoA become before becoming palmitate
Anabolic processes as a supply of reducing equivalents
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

45. What is the activated carrier for phosphoryl
Change resulting in early stop codon
Night blindness - dry skin
ATP
OTC has hyperammonemia - orotic aciduira does not

46. The pyruvate dehydorgenase complex serves In what reaction: reactants
2 rings
Pyruvate - NAD+ - CoA
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Terminal regions - tropocollagen

47. How many rings do purines have
Actin and myosin
Glycogen and FFA oxidation; glucose conserved for final sprinting
2 rings
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

48. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
IDL
HMG- CoA (HMG- CoA to mevalonate

49. How do labile celss grow and regenerate and What are examples
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Disorder of aromatic amino acid metabolism
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

50. telangiectasia - recrrent epistaxis - skin discolorations - AVMs
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Liver - also in kidney and gut epithelium
Colchicine
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses