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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 is the purpose of the HMP shunt
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
The triphosphate bond
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
CGG

2. What substances inhibit phosphofructokinase -1
Reads usual codon but inserts wrong AA
Antibiotic use or excessive ingestion of raw eggs
Same AA - often base change in 3rd position of codon (tRNA wobble)
ATP - citrate

3. Name as many x- linked recessive disorders as you can

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4. What happens in vit B2 def
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Nature and severity of phenotype vary from 1 individual to another - NF type 1

5. What regulates whether FBPase -2 or PFK-2 is active
Protein kinase A
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
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)
Superoxide dismutase

6. What is a nonsense mutation
Change resulting in early stop codon
Protective against malaria
Marasmus - muscle wasting
Rotenone - CN- - antimycin A - CO

7. What happens in a B12 def
Only processed RNA
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Protein
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

8. What else can phosphoylate phosphorylase kinase
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Cartilage - hyaline - vitreous body - nucleus pulposus
Ca/calmodulin in muscle to coordinate with muscle activity
PFK - rate limiting enzyme

9. When does aspartate enter the urea cycle
After citruline
IMP precursor
Degredation of dietary TG in small intestine
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons

10. What is a silent mutation
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
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Same AA - often base change in 3rd position of codon (tRNA wobble)
Scrutinizes - hydrolyzes the bond

11. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
HGPRT - defective purine salvage - excess uric acid production
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Transmitted only through mother - all offspring of affected females may show signs of disease
Oxidized hemoglobin precipiated within RBCs

12. nucleotide repeat for fragile x
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
CGG
Uses ATP to add high energy phophate group onto substrate
Prevent strands from reannealing

13. What is regeneration of methionine depedent on...
Poly A polymerase - signal is AAUAA
B12 and folate
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
Chylomicrons

14. What shuttle is used in fatty acid degredation and What does it move and From where to where
Carnitine shuttle - acyl - coa from cyto to mito
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Cyclin dependent kinases;constitutive and inactive
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

15. What is the most abundant protein in the body
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Collagen
Alpha 1 -6 and alpha 1 -4
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

16. What catacholamine step is SAM required for
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Histidine
Conversion of NE to epi
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

17. What is the Name and function of vit B2
Ca/calmodulin in muscle to coordinate with muscle activity
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

18. What metabolic rxns occur in the cytoplasm
Inc CPK and muscle biopsy
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
2 rings
Liver - also in kidney and gut epithelium

19. what gene is implicated in fragile X syndrome - and What is the mutation
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
FMR1 gene - methylation - associated with chromosomal breakage
Orotic acid to UMP
Modifies N- oligosaccharides

20. In a 1000 meter run - Where does energy come from
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
Same as sprint + OXPHOS
Proline and glycine (non glycosylated forms)
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1

21. What is I cell disease
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
NADH - NADPH - FADH2
Inc dicarboxylic acids - dec in glucose and ketones

22. What chromosome is the NF gene on...
IMP precursor
Myeloperoxidase
17 - 17 letters in von Recklinghausen
Malapsorption syndromes like sprue or CF or mineral oil intake

23. What shuttle is involved in fatty acid synthesis and What does it move From where to where
Inhibits the Na/K pump by binding the K side
Lysine and arginine
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Citrate - acetyl coa from mito to cyto

24. What is the RDE of glycogenolysis
Liver and leafy veggies
3' end (with CCA)
Glycogen phosphorylase
Dermatitis - enteritis - alopecia - adrenal insuff

25. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
17 - 17 letters in von Recklinghausen
HMP shunt
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

26. What is NADPH used for
FAP
Degredation of dietary TG in small intestine
Anabolic processes as a supply of reducing equivalents
DNA

27. What happens in vit D excess
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Fructose 1 -6 bisphosphate
Von hippel lindau - 3

28. What happens with wet beriberi
Inc vit B6
High output cardiac failure - dilated cardiomyopathy - edema
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Leu - lys

29. What substances induce phosphofructokinase
AMP - fructose 2 -6 BP
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Glycogen synthase

30. What is Gowers maneuver
Glycine - aspartate - glutamine
CGG
Assistance of upper extremities to stand up
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia

31. Type IV collagen
Phosphofructokinase 1
Malabsorption and steatorrhea (ADEK)
Basement membrane or basal lamina
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

32. How is ATP used by the cell
Degredation of TG circulating in chylomicrons and VLDLs
ATP hyrdolysis couple to energetically unfavorable rxns
P+q = 1
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O

33. What is heteroplasmy
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Seals.
Dopamine beta hydroxylase
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

34. When are glycogen reserves depleted
Ribos first then deoxyribos with ribonucleotide reductase
Poly A polymerase - signal is AAUAA
After day 1
Nissl body - enzyme and NTs

35. What is the energy source for tRNA actication (charging)
Covalent cross - linking by lysyl oxidase to make collagen fibrils
ATP
Acetly- CoA - CO2 - NADH
UDP glucose pyrophosphorylase

36. What is the RDE of cholesterol synthesis
Failure to track objects or develop a social smile
HMG- CoA reductase
The triphosphate bond
Bind 30s subunit preventing attachment of aminoacyl - tRNA

37. 1 g of protein or cabrohydrate = ?kcal
Prevent strands from reannealing
Alpha1 antitrypsin
Four
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

38. What causes maple syrup urine disease and What does it lead to...
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
Tuberous sclerosis
Glutamine PRPP amidotransferase
Post to neg

39. What is DNA cloning and How do you do it?
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Inhibits the Na/K pump by binding the K side
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

40. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Glycine
Changed AA (convservative - new AA is similar in chemical structure)
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Transmitted only through mother - all offspring of affected females may show signs of disease

41. What is the fxn of vit K
2 -4 DNP - aspirin
Von gierkes - glucose 6 phosphatase
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Breaks down acyl - coa to acetyl coa groups in mito

42. What does biotin def cause
Tryptophan
Dermatitis - alopecia - enteritis
Mutated dystrophin gene - less severe - adolescence
Liver and leafy veggies

43. What converts DOPA to dopamine
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Dopa decarboxylase
Neural tube
Defect in fibrillin

44. What feedback inhibits hexokinase
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
G6PD
Glucose -6 phosphate
2 rings

45. What is the function of biotin
ATP hyrdolysis couple to energetically unfavorable rxns
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Dermatitis - glossitis - and diarrhea

46. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Not all individuals with a mutant genotype show the mutant phenotype
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Flagella - cilia - mitotic spindles
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood

47. What is the energy source after day 3 of starvation
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
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Acetoacetate and beta hydroxybutyrate
IMP precursor

48. What is the results of vit B1 def
Keep glutathione reduced so it can detoxify free radicals and peroxides
Base + ribose + phosphate (3' -5') phosphodiester bond
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

49. What is the amino acid precursor for histamine
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Stop codon is recognized by release factor - and completed protein is released from ribosome
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Histidine

50. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
Neimann - pick - sphingomyelinase - sphingomyelin - AR
In ER - glucose 6- P to glucose
Tryptophan
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible