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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 fatty acid synthesis
Glycogen and FFA oxidation; glucose conserved for final sprinting
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Acetyl - CoA carboxylase (ACC)
No - its non homologous

2. What is the result of vit B5 def
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine

3. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
CAG - 4
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
30 - glycerol -3- phosphate shuttle

4. Of the four possible fates for pyruvate - which ends anaerobic glycolysis as in RBCs - leukocytes - kidney medulla - lens - testes and cornea
B12 and folate
Kwashiorkor - small child with swollen belly
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Lactate

5. What is the TX for PKU
Changed AA (convservative - new AA is similar in chemical structure)
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Silencers
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

6. What does lipoprotein lipase do
Degredation of TG circulating in chylomicrons and VLDLs
2 rings
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

7. What enzyme adds Cl - to the H202 to makes bleach
Phenytoin - MTX - and sulfonamides
Myeloperoxidase
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
5' of the incoming nucleotide

8. What are the functinos of vitamin A
Particular sequence of DNA where replicatino begins - may be single of multiple
Abnormal protein folding - degradation before reaching cell surface
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

9. What does a decrease in decrease in NADPH lead to and why
Inc dicarboxylic acids - dec in glucose and ketones
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Microtubules
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

10. In what cells do the respiratory burst occur
PMNs
DNA
Same AA - often base change in 3rd position of codon (tRNA wobble)
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive

11. What is the TX for hyper ammonemia
Tropoelastin with fibrillin scafolding
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Glutamine PRPP amidotransferase
Orotic acid to UMP

12. What bone disorder has x linked dominant inheritance
Base + ribose
Acetyl - CoA
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
O- oligosaccharaides

13. Which phase of the HMP shunt is reversible and Which is irreversible
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
FMR1 gene - methylation - associated with chromosomal breakage
Active secretion in lungs and GI - reabsorbs in skin
Oxidative is irreversible

14. What enzyme turns ROS to H2O2
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Degradation of TG remaining in IDL
Superoxide dismutase
Diphyllobothrium latum

15. What does Alports syndrome cause and why
ADPKD
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
2pq
AMP - fructose 2 -6 BP

16. What shuttle is used in fatty acid degredation and What does it move and From where to where
Antibiotic use or excessive ingestion of raw eggs
Carnitine shuttle - acyl - coa from cyto to mito
Glycine
Pyruvate to oxaloacetate (3C to 4C)

17. What feedback inhibits hexokinase
EtOH dehydrogenase and acetaldehyde dehydrogenase
Glucose -6 phosphate
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Free ribosomes

18. What substance inside the cell serves to oxidize glutatione
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Peroxide
THFs

19. What does beta oxidation do and Where does it occur
Achondroplasia
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin
Breaks down acyl - coa to acetyl coa groups in mito
Antioxidant - protects RBCs and membrances from free radical damage

20. recurrent pulmonary infxns in CF are due to what organisms
Proline and lysine - vit C
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Pseudomonas and s aureus
Accelearted muscle breakdown

21. Where are FADH2 electrons transferred to...
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Comlex II
Acetly- CoA - CO2 - NADH

22. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Inc glucagon - inc cAMP - inc PKA
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Sucrose = glucose + fructose - lactose = glucose + galactose
Alanine

23. What reaction does adenosine deaminase normally catalyze
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Adenosine to inosine
CarTWOlage

24. What produces NADPH
NADH - NADPH - FADH2
HMP shunt
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Glutamate

25. in a 100 meter sprint Where does energy come from
Ribose 5- P to PRPP
HDL
RRNA
Stored ATP - creatine phosphate - anaerobic glycolysis

26. What is the trinucleotide repeat in fragile X
Binds 50S - blocking translocation
Arg - lys - his - arg is most basic - has has no charge at body pH
CGG
Carnitine shuttle - acyl - coa from cyto to mito

27. How is orotic aciduria inherited
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Protein
Wrinkles and acne
AR

28. What is the results of vit B1 def
SnRNPs
Base + ribose
II - VII - IX - X (1972) protein C and S
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

29. What is the function of folic acid
Tropoelastin with fibrillin scafolding
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
30 - glycerol -3- phosphate shuttle
SnRNPs and other proteins

30. What does primase do
Makes RNA primer on which DNA poly III can initiate replication
RNA poly II
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

31. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Initiate chains
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Inc dicarboxylic acids - dec in glucose and ketones

32. In which state is FBPase -2 active
Fasting
Attachment of ubiquitin to defective proteins tag them for breakdown
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
2 -4 DNP - aspirin

33. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Tuberous sclerosis
Assistance of upper extremities to stand up
SnRNPs
Hereditary spherocytosis

34. What causes biotin def
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Antibiotic use or excessive ingestion of raw eggs
Alpha 1 -4 glucosidase
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

35. What is the defect in cystinuria
Lactate
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
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
TTP

36. What substances are uncouling agents
Asp and Glu
2 -4 DNP - aspirin
Inc melt - dec fluidity
Base + ribose

37. 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
Scrutinizes - hydrolyzes the bond
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
40 - 60 - 80
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

38. The pyruvate dehydrogenase complex serves In what reaction: products
2pq
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Acetly- CoA - CO2 - NADH
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

39. What two pathways is carbomoyl phosphate involved in - and what enzyme deficiency leads to a build of carbamoyl phosphate leading to what element in pyrimidine synthesis
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
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
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

40. What happens at the smooth ER
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Site of steroid synthesis and detoxification of drugs and poisons
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Grows slowly - collapses quickly

41. What is the fxn of vit K
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Fibrofatty replacement of muscle - cardiac myopathy
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

42. central and peripheral demyelination with ataxia and dementia
RRNA
75 to 90 - cloverleaf
Supply sufficient glucose to brain and RBCs and to preserve protein
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

43. What does the CFTR channel do in the lungs - GI tract and skin
Alkaptonuria - may have debiliating arthralgias
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
FAP
Active secretion in lungs and GI - reabsorbs in skin

44. Giving folate during early pregnancy is important to prevent what birth defects
APKD1 on chromosome 16
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Neural tube
Defect in fibrillin

45. I g fat = ? Kcal
Phenylketones in urine
FISH
Nine
PCR - denaturation - annealing - elongation

46. What happens in the first stage of collagen synthesis - and Where does it happen
Fibrofatty replacement of muscle - cardiac myopathy
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Procollagen - triple helix of 3 alpha collagen chains
HGPRT - defective purine salvage - excess uric acid production

47. What does a northern blot use as its sample
HMP shunt
RNA
Initiate chains
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

48. What is a frame shift
FAP
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Inc vit B6
Leu - lys

49. What defects characterize DiGeorge syndrome
Thymic - parathyroid and cardiac
Stop codon is recognized by release factor - and completed protein is released from ribosome
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
Peroxide

50. What is heteroplasmy
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Isocitrate dehydrogenase
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea