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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. Where are cytosolic and organellar proteins made
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Free ribosomes
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
3' end (with CCA)

2. Why enzyme breaks down elastin and what enzyme inhibits it
Elastase - inhibited by alpha1 antitrypsin
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Asp and Glu
Antioxidant - protects RBCs and membrances from free radical damage

3. What is the defect in fructose intolerance and What does it cause
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
ATP hyrdolysis couple to energetically unfavorable rxns
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Alpha 1 -4 glucosidase

4. How many rings do pyrimidines have
Transmitted only through mother - all offspring of affected females may show signs of disease
1 ring
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)
Unwinds DNA template at replcation fork

5. What is the TX for CF and What does it do
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)
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt

6. How do tetracyclines work
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Cartilage - hyaline - vitreous body - nucleus pulposus
Bind 30s subunit preventing attachment of aminoacyl - tRNA

7. What converts DOPA to dopamine
ATP
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
Dopa decarboxylase
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

8. What does a carboxylase do
Adds 2 carbon with the help of biotin
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
HMG- CoA synthase
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

9. In what direction are DNA and RNA synthesized

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10. How do you diagnose CFTR
Inc Cl - in sweat
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Phenylketones in urine
Only processed RNA

11. What is NADPH used for
Anabolic processes as a supply of reducing equivalents
Glutamate
BOne
Euchromatin

12. What converts dopamine to NE
UDP glucose pyrophosphorylase
Inhibits RNA polymerase II - found in death cap mushrooms
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Dopamine beta hydroxylase

13. What does amino acid catabolsim results in the formation of what?
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Nonsense > missense > silent
F16BP
DNA

14. Why can't muscle produce in gluconeogenesis
Lacks glucose 6 phophatase
Medial dorsal nucleus of thalamus - mamillary bodies
Ile - phe - thr - trp
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

15. What is the origin of replication
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Particular sequence of DNA where replicatino begins - may be single of multiple
Alpha 1 -6 and alpha 1 -4
Phenytoin - MTX - and sulfonamides

16. Which aspect of the spliceosome do patients with lupus make antibodies against
SnRNPs
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Foliage - small reserve in liver - eat green leaves
9+2 arrangement of microtubules

17. What causes biotin def
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
CGG
Locus heterogeneity - ocular albinism is x- linked recessive
Antibiotic use or excessive ingestion of raw eggs

18. What substance inside the cell reduces glutatione
NADPH
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Targets the proteins for lysosome

19. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
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
L form
CFTR gene - 7 - Phe 508
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

20. What does the primary transcript combine with to form the spliceosome
Stop codon is recognized by release factor - and completed protein is released from ribosome
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
SnRNPs and other proteins

21. What do the single stranded binding proteins do
Tuberous sclerosis
Males are infertile due to bilateral absence of vas deferens
Krabbes - galactocerebrosidase - galactocerebroside - AR
Prevent strands from reannealing

22. What is pleiotropy and given an example
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Cyclin dependent kinases;constitutive and inactive

23. What leads to the deletion of the dystrophin gene in duchenne's muscular dystrophy
Ca/calmodulin in muscle to coordinate with muscle activity
X linked frame shif mutation
HMP shunt
Euchromatin

24. Which tumor suppresors inhibit G1 to S progression - where mutations result in unrestrained growth
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Rb and p53
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Binds to LDL receptor - mediates VLDL secretion

25. 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
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
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Debranching enzyme
Y shaped region along the DNA template where leading nad lagging strands are synthesized

26. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
Specific glycosylases - AP endonuclease
Cre - lox system
B100 and E
SNP

27. What enzymes metabolize fatty acids and amino acids
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Acetoacetate and beta hydroxybutyrate
Removes phosphate group from substrate
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

28. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Peroxide
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE
Marasmus - muscle wasting
Dec DNA - dec lymphos leads to SCID

29. Where is acetaldehyde located
Phenylalanine
Mitochondria
Glucose 6 phosphatase
Failure to track objects or develop a social smile

30. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
30 - 50 - 70
Basement membrane or basal lamina
DTMP

31. What are the only purely ketogenic amino acids
Achondroplasia
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Adenosine to inosine
Lysine and leucine

32. What form of amino acids are found in proteins
Passed to glutamate - then to alanine enters blood - enters liver - coverted to pyruvate and transfers ammonium back to glutamate which gives it to the urea cycle
L form
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -

33. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Type II
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Transmitted through both parents - affected mother may have affected children - affected father will have affected children

34. What is the most abundant type of RNA
Glycine
Dermatitis - enteritis - alopecia - adrenal insuff
Makes RNA primer on which DNA poly III can initiate replication
RRNA

35. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Promotor - TATA box - and CAAT box - AT rich
Fructose 1 -6 bisphosphate
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

36. What CETP do
Tropoelastin with fibrillin scafolding
Elastase - inhibited by alpha1 antitrypsin
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

37. What does lactase deficiency cause
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
ATP hyrdolysis couple to energetically unfavorable rxns
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
1 ring

38. What apolipoprotiens are on VLDL
Medial dorsal nucleus of thalamus - mamillary bodies
Activates LCAT
B-100 - CII and E
SNP

39. What converts NE to epi
Phenylethamolamine N methyl transferase
Transmitted only through mother - all offspring of affected females may show signs of disease
Hyperlipidemia
Change resulting in early stop codon

40. delivers hepatic TGs to peripheral tissue - secreted by liver
VLDL
Cartilage - hyaline - vitreous body - nucleus pulposus
Glutamate
Arg - lys - his - arg is most basic - has has no charge at body pH

41. Type I collagen
Males are infertile due to bilateral absence of vas deferens
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
VLDL
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

42. What fxn does glucokinase serve in the liver
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Inc Cl - in sweat
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

43. What polar group does guanine have - and what non polar group does thymine have
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Chylomicrons
Only processed RNA
Ketone - methyl

44. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Heterochromatin = HighlyCondensed
Acetyl - CoA to malonyl - CoA (2C to 3C)
Failure to track objects or develop a social smile

45. What chromosome is the NF gene on...
Griseofulvin
17 - 17 letters in von Recklinghausen
Degredation of dietary TG in small intestine
Lacks glucose 6 phophatase

46. What is a missense mutation
Changed AA (convservative - new AA is similar in chemical structure)
Must be both activated and inactivated for cell cycle to progress
Glucose - 2Pi - 2ADP - 2NAD+
Read from a fixed starting point as a continuous sequence of bases

47. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
32 - malate aspartate shuttle
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
RRNA

48. What does vit C def cause
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Met - val - arg his
Reads usual codon but inserts wrong AA
Stored ATP - creatine phosphate - anaerobic glycolysis

49. Describe the location and fxn of the Na/K ATPase
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
PFK - rate limiting enzyme
Orotic acid to UMP
CarTWOlage

50. What are ketone bodies made from - where are they metabolized and how are they excreted
By inhibiting formation of the initiation complex and cause misreading of mRNA
Acetyl - CoA to malonyl - CoA (2C to 3C)
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
DNA