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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 is the RDE of gluconeogenesis
RNA
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
HGPRT - defective purine salvage - excess uric acid production
Fructose 1 -6 bisphosphate

2. Where is EtOH dehydrogenase located
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Cytosol

3. What enzyme adds Cl - to the H202 to makes bleach
Acetyl - CoA
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Myeloperoxidase
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

4. What does aminoacyl tRNA synthetase do the AA before and after it binds to tRNA - and what happens if it's the wrong the match
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Scrutinizes - hydrolyzes the bond
Peroxide
X linked frame shif mutation

5. The pyruvate dehydorgenase complex serves In what reaction: reactants
Pyruvate - NAD+ - CoA
HVA
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

6. What part of the pre mRNA contains the actual genetic information coding for protein
II - VII - IX - X (1972) protein C and S
Exons
Cofactor for LPL
Tuberous sclerosis

7. Severe fasting hypoglycemia - inc glycogen storage in liver - inc blood lactate - hepatomegaly - dz and def enzyme
LCAT (lecithin cholesterol acyltransferase)
Von gierkes - glucose 6 phosphatase
Acetly- CoA - CO2 - NADH
Inhibit DNA gyrase specific for prokaryotic topoisomerase

8. What does lactase deficiency cause
HVA
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

9. What does Alports syndrome cause and why
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
Marasmus - muscle wasting
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

10. What tissue samples are used for karyotyping
Neither of 2 alleles is dominant - blood groups
Blood - bone marrown - amniotic fluid - placental tissue
Euchromatin
CGG

11. Which RNA poly opens DNA at promotor site
Rb and p53
RNA poly II
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
ATP

12. what findings are associated with marfans
Oral uridine administration
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
TRNA
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly

13. What is disulfiram used for
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Four
O- oligosaccharaides

14. What enzyme results in classic galactosemia and What is the clinical
Microarrays
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Grows slowly - collapses quickly
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation

15. What are the symptoms of vit A def
5' to 3'
Night blindness - dry skin
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
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

16. What substances directly inhibit electron transport chain
Rotenone - CN- - antimycin A - CO
B-100 - CII and E
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
CarTWOlage

17. Type III collagen
Glucose - 2Pi - 2ADP - 2NAD+
Vincritsine/vinblastine
Basement membrane or basal lamina
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue

18. What happens at the smooth ER
Site of steroid synthesis and detoxification of drugs and poisons
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
APC on chromosome 5
Removes phosphate group from substrate

19. What activates the pyruvate dehydrogenase complex
LCAT (lecithin cholesterol acyltransferase)
Exercise: inc NAD/NADH - inc ADP - inc Ca
NAD+
Inc vit B6

20. What kind of branches do glycogen branches have
Alpha 1 -6 and alpha 1 -4
FMR1 gene - methylation - associated with chromosomal breakage
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
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx

21. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
32 - malate aspartate shuttle
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Hypoglycemia

22. What substance in egg whites binds biotin
Avidin
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 Cl - in sweat
Phenylalanine hydroxylase

23. What does lipoprotein lipase do
Degredation of TG circulating in chylomicrons and VLDLs
Modifies N- oligosaccharides
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Tuberous sclerosis

24. What is the Name and function of vit B1
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Ile - phe - thr - trp

25. 90% of ADPKD cases are due to a mutation In what gene
Result from phagocytic removal of heinz bodies my macs - G6PD def
APKD1 on chromosome 16
Oxidative and nonoxidative - no ATP produced or used
Phenylalanine

26. What is the energy source for translocation
Chylomicrons
Biotin
GTP
Inc melt - dec fluidity

27. What is chediak higashi
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Night blindness - dry skin
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Abnormal protein folding - degradation before reaching cell surface

28. What produces NADPH
2 rings
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
HMP shunt
1 -25 OH2 D3 = calcitriol

29. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Dermatitis - glossitis - and diarrhea
FAP
Colchicine

30. What apolipoprotiens are on VLDL
B-100 - CII and E
2 rings
2 -4 DNP - aspirin
ATP hyrdolysis couple to energetically unfavorable rxns

31. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Inc melt - dec fluidity
Huntingtons
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Nonsense > missense > silent

32. What does a phosphatase do
Pseudomonas and s aureus
Debranching enzyme
Removes phosphate group from substrate
UGA - UAA and UAG

33. What is the result of vit B5 def
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
B-100 - CII and E
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

34. What does DNA poly I do?
Neither of 2 alleles is dominant - blood groups
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
ATP

35. What enzyme degrades a small amount of glycogen in lysosomes
Alpha 1 -4 glucosidase
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Carnitine acyltransferase I
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

36. A small proportion of Down syndrome is due to What two genetic events
PCR - denaturation - annealing - elongation
Robertsonian translocation and mosaicism
Met - val - arg his
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

37. What is linkage disequilibrium
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Actin and myosin
Result from phagocytic removal of heinz bodies my macs - G6PD def

38. What does hartnups disease cause
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Fibrofatty replacement of muscle - cardiac myopathy
Promotor - TATA box - and CAAT box - AT rich
Neural tube

39. What does a kinase do
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
Uses ATP to add high energy phophate group onto substrate
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Malabsorption and steatorrhea (ADEK)

40. What is the amino acid precursor for porphyrin and heme
Glycine
Rb and p53
Kwashiorkor - small child with swollen belly
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis

41. When does aspartate enter the urea cycle
Result from phagocytic removal of heinz bodies my macs - G6PD def
Cre - lox system
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
After citruline

42. What does the deletion of the dystrophin gene lead to...
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Arginine
CGG
Accelearted muscle breakdown

43. Broadly - What can cause fat - soluble vitamin deficiencies
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Eu - methionine - pro - formyl - methionine
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Malapsorption syndromes like sprue or CF or mineral oil intake

44. What tissues have both enzymes of sorbitol metabolism
III - joint dislocation - anuerysms - organ rupture
Result from phagocytic removal of heinz bodies my macs - G6PD def
APKD1 on chromosome 16
Liver - ovaries - seminal vesicles

45. What substances inhibit phosphofructokinase -1
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Night blindness - dry skin
ATP - citrate
25OHD3

46. What happens in hyperammonemia
Read from a fixed starting point as a continuous sequence of bases
RNA poly II
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

47. central and peripheral demyelination with ataxia and dementia
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
2 rings
The triphosphate bond
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

48. What is the active form of vit D
GAA
Polyneuritis - symmetrical muscle wasting
1 -25 OH2 D3 = calcitriol
Thymic - parathyroid and cardiac

49. What causes patau's syndrome and What is it
Tropoelastin with fibrillin scafolding
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Flank pain - hematuria - HTN - progressive renal failure

50. 1 g of protein or cabrohydrate = ?kcal
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Four
Glycogen synthase
Free ribosomes