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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 amino acid makes up most of the octamer
Diphyllobothrium latum
PCR - denaturation - annealing - elongation
Lysine and arginine
N to C

2. What are the two transgenic strategies in mice
Night blindness - dry skin
Result from phagocytic removal of heinz bodies my macs - G6PD def
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Change resulting in early stop codon

3. What does Alports syndrome cause and why
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
MRNA
Leu - lys
Liver and leafy veggies

4. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Autosomal recessive diseases
Glucose - 2Pi - 2ADP - 2NAD+
Terminal regions - tropocollagen
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

5. In which state is PFK-2 active
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Fed
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Cre - lox system

6. What is the amino acid precursor for histamine
Histidine
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
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra

7. What do B- complex vitamin deficiencies often result in
N to C
Superoxide dismutase
Dermatitis - glossitis - and diarrhea
Blood - bone marrown - amniotic fluid - placental tissue

8. What are possilbe presentation for galactokinase def
No
Failure to track objects or develop a social smile
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor

9. What causes Hartnup's disease
X- linked recessive
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

10. What does the vimentin stain for
L form
Connective tissue
Adenosine to inosine
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

11. characterize x linked recessive
O- oligosaccharaides
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
Asp and Glu
TTP

12. Type II collagen
HMG- CoA (HMG- CoA to mevalonate
Cartilage - hyaline - vitreous body - nucleus pulposus
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Makes RNA primer on which DNA poly III can initiate replication

13. What does glycosylation of pro alpha chian yield and What is the structure
Arginine
Procollagen - triple helix of 3 alpha collagen chains
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Adds 2 carbon with the help of biotin

14. What is the Name and function of vit B1
Pyruvate - NAD+ - CoA
DTMP
Phenytoin - MTX - and sulfonamides
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

15. What does acetyl - CoA become before becoming palmitate
After citruline
Kidney - ears - eyes
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

16. Type III collagen
Base + ribose
Kwashiorkor - small child with swollen belly
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Stop codon is recognized by release factor - and completed protein is released from ribosome

17. What is the order of severity for the different types of mutations
Dopamine beta hydroxylase
Cri du chat
Nonsense > missense > silent
Fibroblast

18. What does cytokeratin stain for
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
Chylomicrons
Epithelial cells
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

19. What is mosaicism and give an example
RER
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
Result from phagocytic removal of heinz bodies my macs - G6PD def
Arginine

20. What substances directly inhibit electron transport chain
Post to neg
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
High output cardiac failure - dilated cardiomyopathy - edema
Rotenone - CN- - antimycin A - CO

21. What is the result of vit B5 def
Dermatitis - enteritis - alopecia - adrenal insuff
1 -25 OH2 D3 = calcitriol
B6
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

22. Is there any requirement for homology in NHEJ
Foliage - small reserve in liver - eat green leaves
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Neuralgia
No - its non homologous

23. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Huntingtons
Dopa decarboxylase
Terminal regions - tropocollagen

24. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
Autosomal recessive diseases
Catabolic processes to carry reducing equivalents away as NADH
ATP hyrdolysis couple to energetically unfavorable rxns
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

25. Very Poor Carbohydrate Metabolism stands for 4 of the glycogen storage diseases - What are thy

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26. What does the golgi add to serine and threonine residues
Peroxide
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
O- oligosaccharaides
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive

27. What happens in vit D excess
Assistance of upper extremities to stand up
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Glutamine PRPP amidotransferase
Procollagen - triple helix of 3 alpha collagen chains

28. What catacholamine step is SAM required for
Conversion of NE to epi
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
IDL
Dermatitis - enteritis - alopecia - adrenal insuff

29. What is the composition of urea and where do each part derive from
Initiate chains
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

30. What converts DOPA to dopamine
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Dopa decarboxylase
Inc vit B6

31. What is the longest time of RNA and shortest
Essential fructosuria - fructokinase AR
MRNA - tRNA
One
Phenylethamolamine N methyl transferase

32. 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
N to C
Methionine encode by only 1 codon (AUG)
Krabbes - galactocerebrosidase - galactocerebroside - AR

33. What does a dehydrogenase do
B12 and folate
Carnitine acyltransferase I
Oxidizes substrate
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

34. What stretch of DNA that alters gene expression by binding of transcription factors
Heterochromatin = HighlyCondensed
4 under the floor
3' end (with CCA)
Enhancers

35. Type IV collagen
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Nine
Basement membrane or basal lamina
Unmethylated - newly synthesized - HNPCC

36. What is the main source of folate
Foliage - small reserve in liver - eat green leaves
TTP
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Inhibits RNA polymerase II - found in death cap mushrooms

37. Accurate base pairing is required only in the first two nucleotide positions of an mRNA codon - so conds differeing in the 3rd position may code for the same tRNA/AA due to degenerate genetic code
L form
Wobble
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

38. What leads to the deletion of the dystrophin gene in duchenne's muscular dystrophy
Dermatitis - glossitis - and diarrhea
Superoxide dismutase
X linked frame shif mutation
Dermatitis - enteritis - alopecia - adrenal insuff

39. What enzyme adds Cl - to the H202 to makes bleach
Myeloperoxidase
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Disorder of aromatic amino acid metabolism

40. How does chloramphenicol work
Inhibits 50S peptidyltransferase
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
N to C
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

41. What kind of branches do glycogen branches have
UGA - UAA and UAG
Free ribosomes
Alpha 1 -6 and alpha 1 -4
Pyruvate to oxaloacetate (3C to 4C)

42. Mediates reverse cholesterol transport from periphery to liver - acts as respository for apoC an apoE - secreted from both liver and small intestine
17 - 17 letters in von Recklinghausen
HDL
Degredation of TG circulating in chylomicrons and VLDLs
ADPKD

43. What is the amino acid precursor for GABA and glutathione
Glutamate
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
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

44. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Activates LCAT
Chylomicrons
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

45. In which structures do you find microtubules
Flagella - cilia - mitotic spindles
Removes phosphate group from substrate
Conversion of NE to epi
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

46. What shape does the RNA generate during splicing and why?
Lariat shape in order and remove intron precisely and join 2 exons
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
LCAT (lecithin cholesterol acyltransferase)
Elastase - inhibited by alpha1 antitrypsin

47. Why is albinism inheritnace varialbe due to...
Arg - lys - his - arg is most basic - has has no charge at body pH
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Locus heterogeneity - ocular albinism is x- linked recessive
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase

48. What is the RDE of TCA cycle
After day 1
High output cardiac failure - dilated cardiomyopathy - edema
Oxidative is irreversible
Isocitrate dehydrogenase

49. What is I cell disease
Poly A polymerase - signal is AAUAA
RER
9+2 arrangement of microtubules
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

50. What 3 steps in RNA processing occur after transcription

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