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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 does apoE do
Achondroplasia
Mediates extra remnant take up
Mitochondria
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

2. What does the primary transcript combine with to form the spliceosome
Hyperlipidemia
SnRNPs and other proteins
Glycogen and FFA oxidation; glucose conserved for final sprinting
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

3. What is axonemal dynein
FMR1 gene - methylation - associated with chromosomal breakage
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
B-100 - CII and E
5' of the incoming nucleotide

4. Wgat substances directly inhibit mitochondrial ATPase - causing an inc in proton gradient - no ATP because pump is stopped
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Dermatitis - enteritis - alopecia - adrenal insuff
Oligomycin

5. What step of uric acid synthesis does xanthine oxidase catalyze
Glucose 6 phosphate dehydrogenase (G6PD)
MRNA - tRNA
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Hypoxanthine to xanthing and xanthine to uric acid

6. What are the findings in Down's syndrome
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
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
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
CAG - 4

7. What kind of RNA is transported out of the nucleus
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
HMG- CoA reductase
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Only processed RNA

8. Which enzyme involved in RNA synthesis does not require a template
Fed
Dopamine beta hydroxylase
Poly A polymerase - signal is AAUAA
Acetyl - CoA

9. ADPKD is associated with What additional conditions
Base + ribose + phosphate (3' -5') phosphodiester bond
5' to 3'
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Hypoxanthine to xanthing and xanthine to uric acid

10. What are the results of pancreatic insuff in CF
Marasmus - muscle wasting
Alpha1 antitrypsin
Malabsorption and steatorrhea (ADEK)
Nature and severity of phenotype vary from 1 individual to another - NF type 1

11. caf
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Neurofibromatosis type 1 (von Recklinghausens disease)
Flagella - cilia - mitotic spindles
Schilling test

12. Where is EtOH dehydrogenase located
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Cytosol
Wrinkles and acne
Marfans

13. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Marasmus - muscle wasting
Autosomal recessive diseases
III - joint dislocation - anuerysms - organ rupture
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

14. What is Gowers maneuver
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Carbomoyl phosphate synthetase I
Assistance of upper extremities to stand up
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

15. What is the name is fxn of vit B3
Glycine - aspartate - glutamine
Niacin - constituent of NAD and NADP - derived from tryptophan
Nonsense > missense > silent
Breaks down acyl - coa to acetyl coa groups in mito

16. Which cells are rich in smooth ER
ATP hyrdolysis couple to energetically unfavorable rxns
Liver hepatocytes and steroid producing cells of the adrenal cortex
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Mucus secreting globlet cells and antibody secreting plasma cells

17. What are the complications/signs of familial hypercholesterolemia
Failure to track objects or develop a social smile
LDL
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Familial hypercholesterolemia - hyperlipidemia type IIA

18. What are the purely ketogenic amino acids
Leu - lys
1 ring
Seals.
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia

19. What does a phosphatase do
Changed AA (convservative - new AA is similar in chemical structure)
Removes phosphate group from substrate
Oxidizes substrate
Deamination

20. Which antihelminthe drugs work on microtubules
Tryptophan
Mebendazole/thiabendazole
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)

21. What is the rate determining enzyme (RDE) of glycolysis
Polyneuritis - symmetrical muscle wasting
9+2 arrangement of microtubules
Phosphofructokinase 1
Adds an inorganic phosphate onto substrate without using ATP

22. What happens in elongation of protein synthesis

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23. In which structures do you find microtubules
Dermatitis - alopecia - enteritis
Flagella - cilia - mitotic spindles
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Breaks down acyl - coa to acetyl coa groups in mito

24. What does hormone sensitive lipase do
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Degradation of TG stored in adipocytes
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR

25. How do microtubules grow and collapse
Schwann cells - lens - retina - kidneys
VMA
Grows slowly - collapses quickly
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor

26. Mediates reverse cholesterol transport from periphery to liver - acts as respository for apoC an apoE - secreted from both liver and small intestine
HDL
Arginine
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR

27. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
Acetyl - CoA
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

28. What is loss of heterozygosity and give an example
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
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
Consesus sequenec of base pairs
Unwinds DNA template at replcation fork

29. decreases In what substances can cause PKU
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase

30. What is the hardy weinberg allele prevalence
P+q = 1
Conversion of NE to epi
Alkaptonuria - may have debiliating arthralgias
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

31. What two proteins make up microtubules and how are they arranged
Protein kinase A
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
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
Alpha and beta tubulin - dimers have two GTP bound

32. What is the activated carrier for Co2
P+q = 1
Biotin
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15

33. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Nonsense > missense > silent
Uses ATP to add high energy phophate group onto substrate
Metanephrine
Familial hypercholesterolemia - hyperlipidemia type IIA

34. What is the rate limiting enzyme in cholesterol synthesis
Transfers methyl units
Tryosine hydroxylase
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
HMG- CoA (HMG- CoA to mevalonate

35. What are uncoupling agents
Tryosine hydroxylase
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
Makes RNA primer on which DNA poly III can initiate replication

36. What are pyrimidines made from
Kwashiorkor - small child with swollen belly
Tyrosine
Polyneuritis - symmetrical muscle wasting
Orotate precursor - with PRPP added later

37. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
Krabbes - galactocerebrosidase - galactocerebroside - AR
Palate - facial and cardiac defects
Zero
Same AA - often base change in 3rd position of codon (tRNA wobble)

38. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Phenytoin - MTX - and sulfonamides
Pyruvate - NAD+ - CoA

39. In the chromatin structure - which histones form the octamer - and which ties the nucleosome beads together in a string?
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Terminal regions - tropocollagen
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

40. Which carbon bears the triphosphate and the energy source for bond formation

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41. What does PURe As Gold and CUT The Py stand for
Sucrose = glucose + fructose - lactose = glucose + galactose
Purines= A - G pyrimidine = C - T (U)
NADPH
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

42. What are the findings in Lesch - Nyhan
Rb and p53
Site of steroid synthesis and detoxification of drugs and poisons
Alpha1 antitrypsin
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

43. What is the composition of urea and where do each part derive from
Active secretion in lungs and GI - reabsorbs in skin
Dec methionine - inc cystiene - inc B12/folate
Diphyllobothrium latum
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

44. What does DNA ligase do
Oxidized hemoglobin precipiated within RBCs
Skin
Failure to track objects or develop a social smile
Seals.

45. This is the site where negative regulators bind
PMNs
Silencers
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

46. What does the vimentin stain for
Connective tissue
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
FAP

47. What are the results of unbalanced translocation
Schwann cells - lens - retina - kidneys
Essential fructosuria - fructokinase AR
Ribos first then deoxyribos with ribonucleotide reductase
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

48. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Cleft palate - cardiac abnl - pregs test
CFTR gene - 7 - Phe 508
Histidine
Pyruvate to oxaloacetate (3C to 4C)

49. FAP is due to deletion On what gene On what chromosome
APC on chromosome 5
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Elastase - inhibited by alpha1 antitrypsin

50. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Heterochromatin = HighlyCondensed
Huntingtons
Paclitaxel
ADPKD