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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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This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Where is vit A found in the diet
Cleft palate - cardiac abnl - pregs test
Liver and leafy veggies
MRNA - tRNA
Mediates extra remnant take up

2. How does insulin inhibit glycogenolysis
Failure to track objects or develop a social smile
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
ATP hyrdolysis couple to energetically unfavorable rxns

3. characterize x linked dominant
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
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
No
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

4. What substance inside the cell serves to oxidize glutatione
Peroxide
ATP
AMP - fructose 2 -6 BP
Base + ribose

5. What amino acid makes up most of the octamer
Lysine and arginine
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Must be both activated and inactivated for cell cycle to progress
Malapsorption syndromes like sprue or CF or mineral oil intake

6. Describe the structure of cilia
Transfers methyl units
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
9+2 arrangement of microtubules
DsRNA promotes degradation of target mRNA knocking down gene expression

7. What is the activated carrier for Acyl
Flank pain - hematuria - HTN - progressive renal failure
Coenzyme A - lipoamide
Kwashiorkor - small child with swollen belly
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1

8. What does Ehlers Danlos cause and why
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Alpha - ketoglutarate dehydrogenase complex
Krabbes - galactocerebrosidase - galactocerebroside - AR
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

9. What else can phosphoylate phosphorylase kinase
Initiate chains
Fructose 1 -6 bisphosphate
Glycogen and FFA oxidation; glucose conserved for final sprinting
Ca/calmodulin in muscle to coordinate with muscle activity

10. What substance in egg whites binds biotin
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Avidin
NADPH
Oxidative is irreversible

11. In which direction is protein synthesized
30 - glycerol -3- phosphate shuttle
N to C
Inhibits the Na/K pump by binding the K side
Lacks glucose 6 phophatase

12. What does Citrate Is Krebs starting substrate for making oxaloacetate
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Ca/calmodulin in muscle to coordinate with muscle activity
Carbomoyl phosphate synthetase II

13. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Oxalacetate
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Proline and lysine - vit C

14. How many rings do pyrimidines have
1 ring
Silencers
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
HVA

15. What causes biotin def
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Mitochondria
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
Antibiotic use or excessive ingestion of raw eggs

16. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
CG- 3 > AT-2 - More CG content - melting point goes up
Tuberous sclerosis
Microarrays
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

17. Type II cartilage
VLDL
Pseudomonas and s aureus
Alcohol version of glucose - can trap glucose in cell - aldose reductase
CarTWOlage

18. deletion of VHL gene on chromosome 3 leading to hemangioblastomas of retina/cerebellum/medulla bilateral RCC - dz and overexpression product
Polycystic liver disease - berry aneurysm - mitral valve prolapse
ATP and methionine
Adds an inorganic phosphate onto substrate without using ATP
Von hippel lindau - 3

19. What does an umabiguous genetic code refer to...
Liver and leafy veggies
Inc vit B6
Wernicke - korsakoff - dry and wet beriberi
Each codon specifies only 1 amino acid

20. bilateral acoustic schwannomas - juvenile cataracts
NF2 on chromosome 22
Terminal regions - tropocollagen
Glycogenolysis to form glucose
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

21. Where is acetaldehyde located
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Von hippel lindau - 3
Mitochondria
AR

22. What are pyrimidines made from
Modifies N- oligosaccharides
Orotate precursor - with PRPP added later
Microtubules
Nature and severity of phenotype vary from 1 individual to another - NF type 1

23. What order kinetics does EtOH dehydrogenase have
Zero
Diphyllobothrium latum
APRT + PRPP
Williams syndrome

24. What does a western blot use for its sample
Krabbes - galactocerebrosidase - galactocerebroside - AR
Protein
Elastase - inhibited by alpha1 antitrypsin
4 under the floor

25. What happens in vit B2 def
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Stop codon is recognized by release factor - and completed protein is released from ribosome
Phenylketones in urine
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

26. What is anticipation and give an example
Neural tube
RNA poly II
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons

27. What rxn creates ATP
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Actin and myosin
CGG
Infection - free radicals generated by inflammatory response

28. What is uniparental disomy
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
PCR - denaturation - annealing - elongation
B6
Met - val - arg his

29. Type IV collagen
Two
IMP precursor
Neurons
Basement membrane or basal lamina

30. What is the order of severity for the different types of mutations
Connective tissue
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
HGPRT - defective purine salvage - excess uric acid production
Nonsense > missense > silent

31. What does DNA ligase do
30 - 50 - 70
Seals.
Type II
75 to 90 - cloverleaf

32. Giving folate during early pregnancy is important to prevent what birth defects
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
AR
Neural tube

33. What are the functinos of vitamin A
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
B48 - AIV - CII - E
Inc Cl - in sweat
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

34. What kind of branches do glycogen branches have
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Alpha 1 -6 and alpha 1 -4
In ER - glucose 6- P to glucose
17 - 17 letters in von Recklinghausen

35. What is chediak higashi
75 to 90 - cloverleaf
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Inc CPK and muscle biopsy
Polyneuritis - symmetrical muscle wasting

36. What is the main source of folate
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Polyneuritis - symmetrical muscle wasting
AMP - fructose 2 -6 BP
Foliage - small reserve in liver - eat green leaves

37. Which are the basic amino acids
Antioxidant - protects RBCs and membrances from free radical damage
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Arg - lys - his - arg is most basic - has has no charge at body pH
Debranching enzyme

38. in a 100 meter sprint Where does energy come from
Protein
Stored ATP - creatine phosphate - anaerobic glycolysis
Inhibits the Na/K pump by binding the K side
More than 1 codon may code for the same amino acid

39. Which antifungal drugs work on microtubules
Inc Cl - in sweat
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
Griseofulvin
In ER - glucose 6- P to glucose

40. What enzyme becomes essential in PKU
Inc Cl - in sweat
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Phosphofructokinase 1
Tyrosine

41. What happens at the smooth ER
Site of steroid synthesis and detoxification of drugs and poisons
Lysine and leucine
DNA
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

42. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Methionine encode by only 1 codon (AUG)
B6
Autosomal recessive diseases
Q -

43. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
Ribos first then deoxyribos with ribonucleotide reductase
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Mitochondria
Phosphofructokinase 1

44. What happens in the first stage of collagen synthesis - and Where does it happen
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
Huntingtons
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
AMP - fructose 2 -6 BP

45. Which tumor suppresors inhibit G1 to S progression - where mutations result in unrestrained growth
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Rb and p53
Neurons

46. What happens with dry beriberi
Disorder of aromatic amino acid metabolism
Polyneuritis - symmetrical muscle wasting
Fasting
SnRNPs and other proteins

47. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Inc melt - dec fluidity
Silencers
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Oxidative and nonoxidative - no ATP produced or used

48. ADPKD is associated with What additional conditions
SAM
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Oligomycin
Flank pain - hematuria - HTN - progressive renal failure

49. What is the breakdown product of dopamine
HVA
2 -4 DNP - aspirin
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
SnRNPs

50. What is the hardy weinber heterozygote prevalence
Degradation of TG stored in adipocytes
CGG
2pq
HMP shunt