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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 happens in hyperammonemia
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
OTC has hyperammonemia - orotic aciduira does not

2. What is linkage disequilibrium
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Proton gradient
Essential fructosuria - fructokinase AR
Antioxidant - protects RBCs and membrances from free radical damage

3. What does Citrate Is Krebs starting substrate for making oxaloacetate
Exons
Inc melt - dec fluidity
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
NADH - NADPH - FADH2

4. What substances inhibit phosphofructokinase -1
Collagen
ATP - citrate
Hyperlipidemia
Karyotyping

5. What 3 syndromes are associated with vit B1 def
Wernicke - korsakoff - dry and wet beriberi
Tryptophan
Mebendazole/thiabendazole
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

6. What apolipoprotein is on LDL
THFs
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
B100
Marfans

7. Who typically has lactase def
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Acetoacetate and beta hydroxybutyrate
African Americans and Asians
RNA

8. What do B- complex vitamin deficiencies often result in
Dermatitis - glossitis - and diarrhea
AR
CGG
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent

9. How is ammonium transported from muscle to the liver for urea cycle
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
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

10. How many ATP are produced by anearobic glycolysis per molecule of glucose
Two
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Mediates extra remnant take up

11. What causes maple syrup urine disease and What does it lead to...
Poly A polymerase - signal is AAUAA
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
DTMP
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

12. What is the composition of urea and where do each part derive from
2pq
Blood - bone marrown - amniotic fluid - placental tissue
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Schilling test

13. Which antifungal drugs work on microtubules
Thymic - parathyroid and cardiac
Griseofulvin
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Rb and p53

14. What does aminoacyl tRNA synthetase do the AA before and after it binds to tRNA - and what happens if it's the wrong the match
Glycine - aspartate - glutamine
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Scrutinizes - hydrolyzes the bond
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

15. What are the purely ketogenic amino acids
RRNA
Glucose 6 phosphate dehydrogenase (G6PD)
Leu - lys
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

16. What is the RDE of cholesterol synthesis
Ribos first then deoxyribos with ribonucleotide reductase
Lariat shape in order and remove intron precisely and join 2 exons
HMG- CoA reductase
Vincritsine/vinblastine

17. What substances induce phosphofructokinase
Same AA - often base change in 3rd position of codon (tRNA wobble)
AMP - fructose 2 -6 BP
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

18. What converts limit dextran to glucose
Epithelial cells
Glutamine PRPP amidotransferase
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Debranching enzyme

19. What are the only purely ketogenic amino acids
Four
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Lysine and leucine
Exons

20. What are the findings in Down's syndrome
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
Neural tube
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
B100

21. What is the defect in II A familial hypercholesterolemia
Nissl body - enzyme and NTs
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
2pq
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

22. What happens at the smooth ER
Alpha1 antitrypsin
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Site of steroid synthesis and detoxification of drugs and poisons
Lariat shape in order and remove intron precisely and join 2 exons

23. What is the rate determining enzyme (RDE) of glycolysis
Phosphofructokinase 1
Blood - bone marrown - amniotic fluid - placental tissue
Uses ATP to add high energy phophate group onto substrate
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

24. What ribosomes do eukaryotes have
ATP - citrate
40 - 60 - 80
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
F16BP

25. What is the defect in fructose intolerance and What does it cause
Citrate - acetyl coa from mito to cyto
THFs
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
IDL

26. What is the amino acid precursor for GABA and glutathione
Acetyl - CoA carboxylase (ACC)
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Glutamate
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

27. What catacholamine step is SAM required for
Conversion of NE to epi
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Removes phosphate group from substrate

28. What are the 4 assumption of the Hardy Weinberg law
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Methionine encode by only 1 codon (AUG)
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

29. What is the activated carrier for methyl groups
Glycogen synthase
Antibiotic use or excessive ingestion of raw eggs
SAM
Griseofulvin

30. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Von Gierke's - Pompe - Cori - McArdle
Type II
Uses ATP to add high energy phophate group onto substrate

31. What are the findings in Lesch - Nyhan
Oxidizes substrate
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
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

32. What does lipoprotein lipase do
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Degredation of TG circulating in chylomicrons and VLDLs
Binds 50S - blocking translocation

33. This is the site where negative regulators bind
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Unwinds DNA template at replcation fork
Silencers
Glucose - 2Pi - 2ADP - 2NAD+

34. What does the golgi assemble proteoglycans from
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Core proteins
Glucose 6 phosphate dehydrogenase (G6PD)
Eu - methionine - pro - formyl - methionine

35. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Dopa decarboxylase
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Keep glutathione reduced so it can detoxify free radicals and peroxides

36. What are the glucogenic/ketogenic amino acids
Ile - phe - thr - trp
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Tuberous sclerosis
Arginine

37. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
Peroxide
LCAT (lecithin cholesterol acyltransferase)
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Ribos first then deoxyribos with ribonucleotide reductase

38. What are the function of vit C
Antibiotic use or excessive ingestion of raw eggs
Fibroblast
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
Exercise: inc NAD/NADH - inc ADP - inc Ca

39. What does DNA poly III do?

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40. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Actin and myosin
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Mitochondria
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins

41. NADPH are used In what 4 things
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Inhibits 50S peptidyltransferase
Essential fructosuria - fructokinase AR
Metanephrine

42. What does hartnups disease cause
Microtubules
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20

43. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
MRNA - tRNA
Conversion of NE to epi
DTMP
UDP glucose pyrophosphorylase

44. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
Thymic - parathyroid and cardiac
CAG - 4
Phenylalanine
Prevent strands from reannealing

45. What two amino acids are required druing periods of growth and why
Arg and his inc in histones Which bind negatively charged DNA
Only processed RNA
2 -4 DNP - aspirin
Adenosine to inosine

46. decreases In what substances can cause PKU
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Must be both activated and inactivated for cell cycle to progress
Acetly- CoA - CO2 - NADH

47. characterize mitochondrial inheritance
Neurofibromatosis type 1 (von Recklinghausens disease)
Lysine and arginine
Microtubules
Transmitted only through mother - all offspring of affected females may show signs of disease

48. What is disulfiram used for
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
HMG- CoA reductase

49. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Consesus sequenec of base pairs
Liver hepatocytes and steroid producing cells of the adrenal cortex
ATP and alanine

50. What is dominant negative mutation and give an example
Familial hypercholesterolemia - hyperlipidemia type IIA
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
Active secretion in lungs and GI - reabsorbs in skin
Binds to LDL receptor - mediates VLDL secretion