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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 enzyme converts phenylalanine to tyrosin
Phenylalanine hydroxylase
Krabbes - galactocerebrosidase - galactocerebroside - AR
5' of the incoming nucleotide
HGPRT - defective purine salvage - excess uric acid production

2. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Glycogen synthase
Arginine
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA

3. characterize x linked dominant
RRNA
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Hereditary spherocytosis
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

4. What are the irreversible enzymes of gluconeogenesis
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
HVA
Core proteins
Covalent cross - linking by lysyl oxidase to make collagen fibrils

5. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Promotor - TATA box - and CAAT box - AT rich
Cre - lox system
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Same as sprint + OXPHOS

6. What is NADPH's role inside RBCs
Isocitrate dehydrogenase
Phenylalanine hydroxylase
Keep glutathione reduced so it can detoxify free radicals and peroxides
Leu - lys

7. what disease can cause pellagra
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Von gierkes - glucose 6 phosphatase
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

8. What does inc phenylalanine lead to...
Phenylketones in urine
Inc CPK and muscle biopsy
Malapsorption syndromes like sprue or CF or mineral oil intake
B100

9. Why can't even chain fatty acids produce new glucose
Alpha1 antitrypsin
Inc melt - dec fluidity
2pq
They yield only acetyl - CoA equivalents

10. What does a defective Cl channel do
After citruline
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Protein kinase A

11. What are the teratogenic effects of vit A and What test must be ordered before starting a woman on isotreitinoin for severe acne
Adenosine to inosine
Cleft palate - cardiac abnl - pregs test
Dec methionine - inc cystiene - inc B12/folate
Foliage - small reserve in liver - eat green leaves

12. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Sucrose = glucose + fructose - lactose = glucose + galactose
Proline and glycine (non glycosylated forms)
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Keep glutathione reduced so it can detoxify free radicals and peroxides

13. What enzyme converts adenine to AMP
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Mucus secreting globlet cells and antibody secreting plasma cells
APRT + PRPP
Huntingtons

14. What components come together to make S- adenosyl methionine
Rotenone - CN- - antimycin A - CO
Ketone - methyl
Q -
ATP and methionine

15. What enzyme does fructose metabolism bypass to reach glycolysis
PFK - rate limiting enzyme
Read from a fixed starting point as a continuous sequence of bases
Basement membrane or basal lamina
Thymic - parathyroid and cardiac

16. For eukaryotes - Where does replication begin?
Terminal regions - tropocollagen
APRT + PRPP
Consesus sequenec of base pairs
Nissl body - enzyme and NTs

17. What are the reactants for glycolysis
Glucose - 2Pi - 2ADP - 2NAD+
SNP
Ribose 5- P to PRPP
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond

18. What is the function of Zinc
Euchromatin
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE

19. What feedback inhibits hexokinase
Glucose -6 phosphate
Cyclin dependent kinases;constitutive and inactive
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Chylomicrons

20. What polar group does guanine have - and what non polar group does thymine have
Ketone - methyl
Von gierkes - glucose 6 phosphatase
Accelearted muscle breakdown
32 - malate aspartate shuttle

21. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Nine

22. What is the RDE of glycogenolysis
Glycogen phosphorylase
Catabolic processes to carry reducing equivalents away as NADH
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Mebendazole/thiabendazole

23. 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
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
F16BP
Inhibits 50S peptidyltransferase

24. Which end of the tRNA is the amino acid bound to...

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25. What happens in vit D excess
Defect in fibrillin
X- linked recessive
Tryptophan
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

26. What is the physiologic role of dystrophin
Inhibits 50S peptidyltransferase
Assistance of upper extremities to stand up
Same as sprint + OXPHOS
Anchor muscle fibers - primarily in skeletal and cardiac muscle

27. Which are the basic amino acids
LDL
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Proline and lysine - vit C
Arg - lys - his - arg is most basic - has has no charge at body pH

28. What is the origin of replication
Particular sequence of DNA where replicatino begins - may be single of multiple
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
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

29. What catacholamine step is SAM required for
Cri du chat
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Conversion of NE to epi

30. What enzyme becomes essential in PKU
Targets the proteins for lysosome
Post to neg
Tyrosine
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

31. What are the blood glucose levels maintained by for days 1-3
Neural tube
Conversion of NE to epi
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Exercise: inc NAD/NADH - inc ADP - inc Ca

32. Where are FADH2 electrons transferred to...
Intermediate filaments
Comlex II
Schilling test
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

33. What lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
PCR - denaturation - annealing - elongation
Microtubules
X- linked recessive
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)

34. What 3 syndromes are associated with vit B1 def
Glycine - aspartate - glutamine
B100 and E
In ER - glucose 6- P to glucose
Wernicke - korsakoff - dry and wet beriberi

35. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Degradation of TG stored in adipocytes
Abnormal protein folding - degradation before reaching cell surface
MEN - 2A and 2B with ret gene
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

36. How do glucagon/epi lead to glycogenolysis
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Post to neg
Fibroblast
Adenosine to inosine

37. What order kinetics does EtOH dehydrogenase have
Proline and lysine - vit C
Zero
Alpha1 antitrypsin
Accelearted muscle breakdown

38. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Oxalacetate
Thymic - parathyroid and cardiac
Terminal regions - tropocollagen
Arg - lys - his - arg is most basic - has has no charge at body pH

39. What enzyme adds Cl - to the H202 to makes bleach
RRNA
Inc glucagon - inc cAMP - inc PKA
Paclitaxel
Myeloperoxidase

40. In which structures do you find microtubules
Eu - methionine - pro - formyl - methionine
Flagella - cilia - mitotic spindles
II - VII - IX - X (1972) protein C and S
Glycine - aspartate - glutamine

41. The pyruvate dehydrogenase complex serves In what reaction: products
Uses ATP to add high energy phophate group onto substrate
Glycine
Acetly- CoA - CO2 - NADH
Kwashiorkor - small child with swollen belly

42. What are the findings in Down's syndrome
PFK - rate limiting enzyme
Lariat shape in order and remove intron precisely and join 2 exons
Two
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

43. What does the TCA cycle produce per 1 acetyl CoA
Cleft palate - cardiac abnl - pregs test
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Dermatitis - glossitis - and diarrhea

44. What is the wernicke - korsakoff clinical picture
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Alpha 1 -6 and alpha 1 -4
Degredation of TG circulating in chylomicrons and VLDLs
Phenylethamolamine N methyl transferase

45. What are pyrimidines made from
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Diphyllobothrium latum
Orotate precursor - with PRPP added later
Metanephrine

46. decreases In what substances can cause PKU
Two
PFK - rate limiting enzyme
Inc Cl - in sweat
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor

47. What is the most abundant protein in the body
Collagen
Robertsonian translocation and mosaicism
Williams syndrome
Attachment of ubiquitin to defective proteins tag them for breakdown

48. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Mediates extra remnant take up

49. What is the amino acid precursor for catecholamines
Von Gierke's - Pompe - Cori - McArdle
Phenylalanine
Rotenone - CN- - antimycin A - CO
Initiate chains

50. What substance accumulates in galactokinase def and What is the clinical picture
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Coenzyme A - lipoamide
N to C