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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. The pyruvate dehydorgenase complex serves In what reaction: reactants
Glycine
Four
Pyruvate - NAD+ - CoA
DNA

2. What enzyme converts glucose 1 p to UDP glucose
Cartilage - hyaline - vitreous body - nucleus pulposus
Von hippel lindau - 3
UDP glucose pyrophosphorylase
Glycine

3. What shuttle is involved in fatty acid synthesis and What does it move From where to where
Citrate - acetyl coa from mito to cyto
Mcardle's - skeletal muscle glycogen posphorylase
Acetoacetate and beta hydroxybutyrate
Q -

4. What does the CFTR channel do in the lungs - GI tract and skin
FAP
Hereditary spherocytosis
Active secretion in lungs and GI - reabsorbs in skin
Phenylalanine

5. What is the RDE of gluconeogenesis
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Fructose 1 -6 bisphosphate
Acetyl - CoA
Four

6. What is the energy source for tRNA actication (charging)
ATP
HMG- CoA (HMG- CoA to mevalonate
ATP and alanine
Inc insulin - dec cAMP - dec PKA

7. FAP is due to deletion On what gene On what chromosome
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
APC on chromosome 5
B6
Cleft palate - cardiac abnl - pregs test

8. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Dec DNA - dec lymphos leads to SCID
Hyperlipidemia
HVA
MEN - 2A and 2B with ret gene

9. What does PURe As Gold and CUT The Py stand for
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Purines= A - G pyrimidine = C - T (U)
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
Conversion of NE to epi

10. What is the source of energy in the fasting state between meals
HDL
APRT + PRPP
ATP hyrdolysis couple to energetically unfavorable rxns
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

11. What is the physiologic role of dystrophin
Fed
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

12. How do microtubules grow and collapse
Dec DNA - dec lymphos leads to SCID
Lactate
5' of the incoming nucleotide
Grows slowly - collapses quickly

13. Which amino acids are elastin rich in
Mediates extra remnant take up
Acetyl - CoA carboxylase (ACC)
Proline and glycine (non glycosylated forms)
CGG

14. 1 g of protein or cabrohydrate = ?kcal
Neuralgia
Vit K antagonist
Reads usual codon but inserts wrong AA
Four

15. What are the characteristics of prader willi syndrome How does it occur
GAA
Ca/calmodulin in muscle to coordinate with muscle activity
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
RER

16. What does inc phenylalanine lead to...
Cartilage - hyaline - vitreous body - nucleus pulposus
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Four
Phenylketones in urine

17. Which antihelminthe drugs work on microtubules
Mebendazole/thiabendazole
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Particular sequence of DNA where replicatino begins - may be single of multiple

18. What substance accumulates in galactokinase def and What is the clinical picture
25OHD3
Oligomycin
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

19. What causes maple syrup urine disease and What does it lead to...
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
RER
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
Glycogen and FFA oxidation; glucose conserved for final sprinting

20. What shape does the RNA generate during splicing and why?
Acetyl - CoA to malonyl - CoA (2C to 3C)
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Lariat shape in order and remove intron precisely and join 2 exons
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

21. What does GFAP stain for
Glycogen and FFA oxidation; glucose conserved for final sprinting
Neuralgia
Sucrose = glucose + fructose - lactose = glucose + galactose
Modifies N- oligosaccharides

22. What happens on the oxidative arm of the HMP shunt and What is the key enzyme
Degradation of TG stored in adipocytes
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
L form

23. What are the results of CF on male fertility
Abnormal protein folding - degradation before reaching cell surface
III - joint dislocation - anuerysms - organ rupture
Males are infertile due to bilateral absence of vas deferens
Karyotyping

24. What is the pathway in the fed state leading to dec FBPase -2 and inc PFK-2
Inc insulin - dec cAMP - dec PKA
Disorder of aromatic amino acid metabolism
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA

25. delivers hepatic TGs to peripheral tissue - secreted by liver
Colchicine
Reads usual codon but inserts wrong AA
VLDL
Anchor muscle fibers - primarily in skeletal and cardiac muscle

26. What does Ehlers Danlos cause and why
Phenytoin - MTX - and sulfonamides
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Dermatitis - glossitis - and diarrhea
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra

27. Which are the acidic amino acids
Asp and Glu
Phenylketones in urine
Myeloperoxidase
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome

28. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
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
Niacin - constituent of NAD and NADP - derived from tryptophan
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

29. What is the result of vit B5 def
Reads usual codon but inserts wrong AA
Alpha1 antitrypsin
B6
Dermatitis - enteritis - alopecia - adrenal insuff

30. What does vit E def cause
RNA
B100
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

31. decreases In what substances can cause PKU
Palate - facial and cardiac defects
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
3' end (with CCA)
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor

32. What happens in vit D excess
Liver hepatocytes and steroid producing cells of the adrenal cortex
SNP
Lacks glucose 6 phophatase
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

33. What is the activated carrier for aldehyddes
Same AA - often base change in 3rd position of codon (tRNA wobble)
TTP
Flank pain - hematuria - HTN - progressive renal failure
GTP

34. What does the TCA cycle produce per 1 acetyl CoA
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Two
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. In eukaryotes - What does RNA poly I make
RRNA
Base + ribose + phosphate (3' -5') phosphodiester bond
RNA
High output cardiac failure - dilated cardiomyopathy - edema

36. What apolipoprotein is on LDL
Avidin
B100
Binds 50S - blocking translocation
HDL

37. What is the prevalence of an X- linked recessive disease in males and in females
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
TTP
MEN - 2A and 2B with ret gene
Q -

38. What are the purely ketogenic amino acids
Activates LCAT
Acetoacetate and beta hydroxybutyrate
After day 1
Leu - lys

39. What does acetyl - CoA become before becoming palmitate
Four
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
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
Transfers methyl units

40. What is pleiotropy and given an example
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Debranching enzyme

41. How is vit D stored
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
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
25OHD3
P2 +2pq+ = 1

42. Where are FADH2 electrons transferred to...
APC on chromosome 5
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
5' to 3'
Comlex II

43. Which phase of the HMP shunt is reversible and Which is irreversible
Oxidative is irreversible
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Read from a fixed starting point as a continuous sequence of bases
Exercise: inc NAD/NADH - inc ADP - inc Ca

44. Which are the basic amino acids
Arg - lys - his - arg is most basic - has has no charge at body pH
Cyclin dependent kinases;constitutive and inactive
Zero
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

45. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
ATP
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Base + ribose
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

46. What does the primary transcript combine with to form the spliceosome
VMA
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
SnRNPs and other proteins
Phosphorylation - glycosylation - hydroxylation

47. What does the vimentin stain for
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Connective tissue
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year
ATP and alanine

48. What 3 steps in RNA processing occur after transcription
Arg and his inc in histones Which bind negatively charged DNA
Free ribosomes
Basement membrane or basal lamina
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns

49. What tissue samples are used for karyotyping
Blood - bone marrown - amniotic fluid - placental tissue
HMG- CoA (HMG- CoA to mevalonate
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

50. What converts tyrosine to DOPA
Tryosine hydroxylase
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
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

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Biochemistry

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