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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 else can phosphoylate phosphorylase kinase
Uses ATP to add high energy phophate group onto substrate
P2 +2pq+ = 1
Ca/calmodulin in muscle to coordinate with muscle activity
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

2. What fxn does glucokinase serve in the liver
Proline and lysine - vit C
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Rotenone - CN- - antimycin A - CO

3. What is the function of biotin
Infection - free radicals generated by inflammatory response
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Stop codon is recognized by release factor - and completed protein is released from ribosome
ATP - citrate

4. What do the single stranded binding proteins do
Lacks glucose 6 phophatase
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Prevent strands from reannealing

5. Where is PEP carboxykinase found - What does it do - and What does it require
Acetyl - CoA
Mcardle's - skeletal muscle glycogen posphorylase
75 to 90 - cloverleaf
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP

6. What two rxns in in glycolysis require ATP
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
No
Collagen
Four

7. Describe the location and fxn of the Na/K ATPase
Glycogen and FFA oxidation; glucose conserved for final sprinting
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
40 - 60 - 80
Neuralgia

8. What neuroanatomical strutures are injured in wernicke - korsakoff
Medial dorsal nucleus of thalamus - mamillary bodies
Disease
TTP
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

9. What are the water soluble vitamins - which ones are stored
After day 1
Phenytoin - MTX - and sulfonamides
Coenzyme A - lipoamide
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

10. What catacholamine step is SAM required for
Glutamine PRPP amidotransferase
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
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Conversion of NE to epi

11. What is the longest time of RNA and shortest
NADPH
NAD+
9+2 arrangement of microtubules
MRNA - tRNA

12. What happens to oxaloacetate in alcholism
No - its non homologous
B100 and E
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

13. What is the RDE of cholesterol synthesis
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
HMG- CoA reductase
African Americans and Asians

14. What part of the pre mRNA contains the actual genetic information coding for protein
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Exons

15. What does hartnups disease cause
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
Acetyl - CoA carboxylase (ACC)
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra

16. What is the breakdown product of NE
VMA
Glucose - 2Pi - 2ADP - 2NAD+
Microtubules
Facial flushing

17. What apolipoproteins are on chylomicrons
Vincritsine/vinblastine
Alpha 1 -4 glucosidase
After citruline
B48 - AIV - CII - E

18. What is a silent mutation
ATP and methionine
Same AA - often base change in 3rd position of codon (tRNA wobble)
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
Adipse tissue stores - keton bodies become the main source of energy fo the brain and heart - after these are depleted - vital protein degradation accelerates - leading to organ failure and death

19. What is the RDE of fatty acid oxidation
40 - 60 - 80
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
B-100 - CII and E
Carnitine acyltransferase I

20. What causes B12 def
Each codon specifies only 1 amino acid
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Neurofibromatosis type 1 (von Recklinghausens disease)
Dopamine beta hydroxylase

21. What is the order of severity for the different types of mutations
Infection - free radicals generated by inflammatory response
G6PD
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Nonsense > missense > silent

22. What is the activated carrier for electrons
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Nonsense > missense > silent
NADH - NADPH - FADH2
Inc melt - dec fluidity

23. What bone disorder has x linked dominant inheritance
Mucus secreting globlet cells and antibody secreting plasma cells
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
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

24. What is the treatment for dec affinity of cystathionine synthase for pyroxidal phosphate
Tryptophan
B100
DsRNA promotes degradation of target mRNA knocking down gene expression
Inc vit B6

25. What are the irreversible enzymes of gluconeogenesis
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Collagen
Inc CPK and muscle biopsy
Polyneuritis - symmetrical muscle wasting

26. What are the clinical features of I cell diesase
After citruline
Exons
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood

27. What enzyme esterifies 2/3 of plasma cholesterol
ADPKD
LCAT (lecithin cholesterol acyltransferase)
CTG
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes

28. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Kidney - ears - eyes
32 - malate aspartate shuttle
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Post to neg

29. What is the hardy weinberg allele prevalence
Inc melt - dec fluidity
5' to 3'
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
P+q = 1

30. What can vit B3 be used to treat
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Attachment of ubiquitin to defective proteins tag them for breakdown
Hyperlipidemia
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns

31. What happens to glycogen in the liver
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Glucose 6 phosphatase
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

32. what findings are associated with marfans
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Vit K antagonist
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Actin and myosin

33. What are the findings with homocystinuria and What amino acid is needs to be supplemented
Acetly- CoA - CO2 - NADH
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Q -

34. What is variable expression and What is an example
Vit K antagonist
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Autosomal recessive diseases
Night blindness - dry skin

35. Severe fasting hypoglycemia - inc glycogen storage in liver - inc blood lactate - hepatomegaly - dz and def enzyme
Von gierkes - glucose 6 phosphatase
Neurons
III - joint dislocation - anuerysms - organ rupture
CAG - 4

36. What is the TX for CF and What does it do
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Proline and glycine (non glycosylated forms)
40 - 60 - 80

37. What does the primary transcript combine with to form the spliceosome
Modifies N- oligosaccharides
Phosphofructokinase 1
SnRNPs and other proteins
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

38. In what cell is collagen synthesis initiated
Binds 50S - blocking translocation
Fibroblast
Antibiotic use or excessive ingestion of raw eggs
Degradation of TG stored in adipocytes

39. What substances induce phosphofructokinase
Deamination
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
AMP - fructose 2 -6 BP

40. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Wernicke - korsakoff - dry and wet beriberi
Inhibits 50S peptidyltransferase
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
4 under the floor

41. What does a decrease in decrease in NADPH lead to and why
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Defect in fibrillin
Epithelial cells
Fructose 1 -6 bisphosphate

42. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Acetyl - CoA to malonyl - CoA (2C to 3C)
Terminal regions - tropocollagen
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms

43. what disease can cause pellagra
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Lactate
Marasmus - muscle wasting
Lariat shape in order and remove intron precisely and join 2 exons

44. What does amino acid catabolsim results in the formation of what?
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Inc CPK and muscle biopsy
Facial flushing
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -

45. What is incomplete penetrence and give an example
Must be both activated and inactivated for cell cycle to progress
Krabbes - galactocerebrosidase - galactocerebroside - AR
Not all individuals with a mutant genotype show the mutant phenotype
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

46. What causes maple syrup urine disease and What does it lead to...
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
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Four
9+2 arrangement of microtubules

47. What rxn does propionyl - CoA carboxylase catalyze
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
CGG
Result from phagocytic removal of heinz bodies my macs - G6PD def
ADPKD

48. What are the only purely ketogenic amino acids
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Lysine and leucine
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

49. In which state is PFK-2 active
Fed
Cytosol
Protein kinase A
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

50. What does a phosphatase do
Removes phosphate group from substrate
Alkaptonuria - may have debiliating arthralgias
Familial hypercholesterolemia - hyperlipidemia type IIA
Dopa decarboxylase