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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 activates the pyruvate dehydrogenase complex
Kwashiorkor - small child with swollen belly
Exercise: inc NAD/NADH - inc ADP - inc Ca
IDL
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

2. What is the energy source for translocation
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
Inc glucagon - inc cAMP - inc PKA
Specific glycosylases - AP endonuclease
GTP

3. What produces NADPH
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Nine
HMP shunt
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

4. What does the CFTR channel do in the lungs - GI tract and skin
IMP precursor
B12 and folate
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Active secretion in lungs and GI - reabsorbs in skin

5. characterize autosomal recessive inheritance
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Each codon specifies only 1 amino acid
30 - glycerol -3- phosphate shuttle
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

6. protein malnutrition resulting in skin lesions - edema and liver malfxn
Passed to glutamate - then to alanine enters blood - enters liver - coverted to pyruvate and transfers ammonium back to glutamate which gives it to the urea cycle
FAP
Kwashiorkor - small child with swollen belly
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive

7. What components come together to make S- adenosyl methionine
ATP and methionine
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Autosomal recessive diseases
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

8. What is chediak higashi
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Williams syndrome
Protein
Carnitine acyltransferase I

9. What does the vimentin stain for
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Connective tissue
Collagen

10. What is the target of the 3' hydroxyl attack
Mediates extra remnant take up
The triphosphate bond
Biotin
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

11. What converts NE to epi
Abnormal protein folding - degradation before reaching cell surface
G6PD
Phenylethamolamine N methyl transferase
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

12. What is the complication of cystinuria
Poly A polymerase - signal is AAUAA
Intermediate filaments
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Uses ATP to add high energy phophate group onto substrate

13. What does vit B3 def result in
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Ribose 5- P to PRPP
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

14. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Inhibits 50S peptidyltransferase
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Degredation of dietary TG in small intestine
Dec DNA - dec lymphos leads to SCID

15. In which direction is protein synthesized
N to C
Transfers methyl units
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Initiate chains

16. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Attachment of ubiquitin to defective proteins tag them for breakdown
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects

17. How does warfarin work
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Flagella - cilia - mitotic spindles
Vit K antagonist

18. Who typically has lactase def
HGPRT - defective purine salvage - excess uric acid production
African Americans and Asians
1 kind with multiple subunits
X- linked recessive

19. Where are cytosolic and organellar proteins made
Free ribosomes
HMP shunt
TRNA
Oral uridine administration

20. What are the characteristics of angelmans syndrome and How does it occur
Reads usual codon but inserts wrong AA
Proline and lysine - vit C
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

21. What is the TX for CF and What does it do
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

22. What are the findings with homocystinuria and What amino acid is needs to be supplemented
MRNA - tRNA
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Type II

23. How do permanent cells grow and regenerate and What are examples of permanent cells
Hypoxanthine to xanthing and xanthine to uric acid
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Wrinkles and acne
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets

24. A small proportion of Down syndrome is due to What two genetic events
Robertsonian translocation and mosaicism
Removes phosphate group from substrate
Failure to track objects or develop a social smile
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

25. In which state is FBPase -2 active
Scrutinizes - hydrolyzes the bond
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Fasting
Enhancers

26. What converts limit dextran to glucose
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
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
Debranching enzyme
Diphyllobothrium latum

27. What is the exception to genetic redundancy
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
Pyruvate to oxaloacetate (3C to 4C)
Ca/calmodulin in muscle to coordinate with muscle activity
Methionine encode by only 1 codon (AUG)

28. How does cytosine become uracil
HMG- CoA (HMG- CoA to mevalonate
Deamination
3' end (with CCA)
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

29. What initiates protein synthesis
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Tyrosine
Base + ribose
Pyruvate to oxaloacetate (3C to 4C)

30. What is a frame shift
Neither of 2 alleles is dominant - blood groups
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Polyneuritis - symmetrical muscle wasting

31. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Glutamine PRPP amidotransferase
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Fibrofatty replacement of muscle - cardiac myopathy

32. What is the defect in II A familial hypercholesterolemia
Locus heterogeneity - ocular albinism is x- linked recessive
Acetyl - CoA to malonyl - CoA (2C to 3C)
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Microarrays

33. What is the RDE of fatty acid synthesis
Phenylalanine hydroxylase
Acetyl - CoA carboxylase (ACC)
Promotor - TATA box - and CAAT box - AT rich
Inc CPK and muscle biopsy

34. What does a northern blot use as its sample
RNA
Comlex II
No
UGA - UAA and UAG

35. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Arg - lys - his - arg is most basic - has has no charge at body pH
Initiate chains
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

36. Where is hexokinase found - What is its Km and Vmax and what uninduces it
Poly A polymerase - signal is AAUAA
Adenosine to inosine
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Degradation of TG stored in adipocytes

37. What is the RDE of ketogenesis
HMG- CoA synthase
Free ribosomes
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Seals.

38. What two proteins make up microtubules and how are they arranged
Purines= A - G pyrimidine = C - T (U)
Post to neg
Alpha and beta tubulin - dimers have two GTP bound
Tryosine hydroxylase

39. What does glycosylation of pro alpha chian yield and What is the structure
Neuralgia
Exons
Procollagen - triple helix of 3 alpha collagen chains
RRNA

40. What is the most abundant type of RNA
Tyrosine
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
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
RRNA

41. What shape does the RNA generate during splicing and why?
Lariat shape in order and remove intron precisely and join 2 exons
Phenylethamolamine N methyl transferase
Antioxidant - protects RBCs and membrances from free radical damage
HMG- CoA synthase

42. What are purines made from
IMP precursor
Deamination
Each codon specifies only 1 amino acid
Coenzyme A - lipoamide

43. What is mosaicism and give an example
Met - val - arg his
ATP hyrdolysis couple to energetically unfavorable rxns
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
Exons

44. What does a defective Cl channel do
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Glucose 6 phosphate dehydrogenase (G6PD)
Acetyl - CoA carboxylase (ACC)

45. What is the treatment for cystathionine synthase def
Phenylethamolamine N methyl transferase
Dec methionine - inc cystiene - inc B12/folate
30 - glycerol -3- phosphate shuttle
Alpha 1 -6 and alpha 1 -4

46. What tissue samples are used for karyotyping
Mediates extra remnant take up
Abnormal protein folding - degradation before reaching cell surface
Blood - bone marrown - amniotic fluid - placental tissue
Histidine

47. What happens in termination of proteins synthesis
Tryosine hydroxylase
Lacks glucose 6 phophatase
Pyruvate to oxaloacetate (3C to 4C)
Stop codon is recognized by release factor - and completed protein is released from ribosome

48. What causes Hartnup's disease
Specific glycosylases - AP endonuclease
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
HGPRT - defective purine salvage - excess uric acid production
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

49. What is the energy source for tRNA actication (charging)
ATP
One
Cofactor for LPL
Palate - facial and cardiac defects

50. How does ethanol induce hypoglycemia
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
HMP shunt
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor