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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. Type I bone
BOne
Active secretion in lungs and GI - reabsorbs in skin
SnRNPs and other proteins
Acetyl - CoA to malonyl - CoA (2C to 3C)

2. Why can't even chain fatty acids produce new glucose
Sulfation
Alkaptonuria - may have debiliating arthralgias
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
They yield only acetyl - CoA equivalents

3. progressive neurodegeneration - developmental delay - cherry red spot on macula - lysosomes with onion skin - NO hepatosplenomegaly
Lactate
Initiate chains
Only processed RNA
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR

4. I g fat = ? Kcal
Nine
Tuberous sclerosis
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1

5. Milder form of type I with nl blood lactate levels - dz and enzyme

6. What happens in vit K def
DTMP
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Isocitrate dehydrogenase
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx

7. What happens with dry beriberi
Polyneuritis - symmetrical muscle wasting
FMR1 gene - methylation - associated with chromosomal breakage
Glutamine PRPP amidotransferase
Active secretion in lungs and GI - reabsorbs in skin

8. How is ammonium transported from muscle to the liver for urea cycle
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Von hippel lindau - 3
Abnormal protein folding - degradation before reaching cell surface
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

9. What causes Hartnup's disease
APRT + PRPP
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Alpha and beta tubulin - dimers have two GTP bound

10. The pyruvate dehydrogenase complex serves In what reaction: products
Purines= A - G pyrimidine = C - T (U)
CarTWOlage
Acetly- CoA - CO2 - NADH
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

11. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Huntingtons
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def

12. what findings are associated with marfans
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Modifies N- oligosaccharides
Myeloperoxidase
Changed AA (convservative - new AA is similar in chemical structure)

13. What does vit E def cause
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Diphyllobothrium latum
1 ring
Inc vit B6

14. What is the defect in fructose intolerance and What does it cause
Acetyl - CoA carboxylase (ACC)
Targets the proteins for lysosome
X linked frame shif mutation
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

15. What are the characteristics of prader willi syndrome How does it occur
Arg - lys - his - arg is most basic - has has no charge at body pH
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Enhancers
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)

16. What apolipoprotiens are on VLDL
HDL
B-100 - CII and E
Fibroblast
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

17. In which state is PFK-2 active
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Nine
Four
Fed

18. What happens to glycogen in the liver
RRNA
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Neither of 2 alleles is dominant - blood groups

19. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Methionine encode by only 1 codon (AUG)
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Mutated dystrophin gene - less severe - adolescence
Sucrose = glucose + fructose - lactose = glucose + galactose

20. What happens in vit B2 def
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
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
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Inc dicarboxylic acids - dec in glucose and ketones

21. What happens in vit D excess
NF2 on chromosome 22
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Specific glycosylases - AP endonuclease
By inhibiting formation of the initiation complex and cause misreading of mRNA

22. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Glycolysis and aerobic respiration
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Acetoacetate and beta hydroxybutyrate

23. What two cells are particularly rich in RER
Vincritsine/vinblastine
Mucus secreting globlet cells and antibody secreting plasma cells
Silencers
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

24. What is uniparental disomy
Liver hepatocytes and steroid producing cells of the adrenal cortex
Males are infertile due to bilateral absence of vas deferens
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent

25. Which cells are rich in smooth ER
Neural tube
THFs
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Liver hepatocytes and steroid producing cells of the adrenal cortex

26. What are cyclins
25OHD3
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
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
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22

27. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Ketone - methyl
CFTR gene - 7 - Phe 508
Bind 30s subunit preventing attachment of aminoacyl - tRNA
RRNA

28. How is ATP used by the cell
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
ATP hyrdolysis couple to energetically unfavorable rxns
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

29. What are bite cells and when do you see them
Result from phagocytic removal of heinz bodies my macs - G6PD def
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive

30. Why does alpha amanitin cause liver failure and Where is it found
G6PD
Tuberous sclerosis
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Inhibits RNA polymerase II - found in death cap mushrooms

31. What leads to the deletion of the dystrophin gene in duchenne's muscular dystrophy
Biotin
PCR - denaturation - annealing - elongation
X linked frame shif mutation
Marasmus - muscle wasting

32. What substance inside the cells replenishes NADPH
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Catabolic processes to carry reducing equivalents away as NADH
Neurofibromatosis type 1 (von Recklinghausens disease)
G6PD

33. In mismatch repair - which strand is recognized and In what hereditary syndrome is this defective
Only processed RNA
Unmethylated - newly synthesized - HNPCC
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome

34. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Actin and myosin
Inc melt - dec fluidity
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
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

35. What converts DOPA to dopamine
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Change resulting in early stop codon
Dopa decarboxylase
Antibiotic use or excessive ingestion of raw eggs

36. What is the activated carrier for 1 carbon units
Seals.
THFs
Polyneuritis - symmetrical muscle wasting
Antigen - antibody reactivity - can look for antigen or antibody in patients blood

37. what disease can cause pellagra
Peroxide
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Hypoglycemia
Base + ribose

38. How do cardia glycosides work
Inc permeability of membrane causing a dec in proton gradient and inc in O2 consumption - ATP synthesis stops - but electron transport continues to produce heat
CGG
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates

39. What enzyme converts phenylalanine to tyrosin
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
LDL
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Phenylalanine hydroxylase

40. What does a northern blot use as its sample
Glucose - 2Pi - 2ADP - 2NAD+
Phenylalanine hydroxylase
MEN - 2A and 2B with ret gene
RNA

41. What initiates protein synthesis
Schwann cells - lens - retina - kidneys
Mediates chylomicron secretion
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Asp and Glu

42. What is the treatment for cystathionine synthase def
CAG - 4
Specific glycosylases - AP endonuclease
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Dec methionine - inc cystiene - inc B12/folate

43. What apolipoproteins are on IDL
Nissl body - enzyme and NTs
Glycolysis and aerobic respiration
Inc glucagon - inc cAMP - inc PKA
B100 and E

44. What is the name is fxn of vit B3
RER
Niacin - constituent of NAD and NADP - derived from tryptophan
Dermatitis - glossitis - and diarrhea
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

45. What is linkage disequilibrium
1 ring
5' to 3'
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

46. What are ketone bodies made from - where are they metabolized and how are they excreted
Neural tube
Promotor - TATA box - and CAAT box - AT rich
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
VLDL

47. 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
Inc vit B6
Glucose 6 phosphate dehydrogenase (G6PD)
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Wobble

48. What is the Name and fxn of vit B5
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Specific glycosylases - AP endonuclease
OTC has hyperammonemia - orotic aciduira does not

49. Describe the location and fxn of the Na/K ATPase
CGG
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

50. In a marathon Where does energy come from
DsRNA promotes degradation of target mRNA knocking down gene expression
Glycogen and FFA oxidation; glucose conserved for final sprinting
Cartilage - hyaline - vitreous body - nucleus pulposus
Tryptophan