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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 other complex is similar to the pyruvate dehydrogenase complex in that it has the same co - factors and generates succinyl - CoA
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
RRNA
N to C
Alpha - ketoglutarate dehydrogenase complex

2. What are the symptoms of vit A def
Night blindness - dry skin
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
ATP and methionine
X linked frame shif mutation

3. What are the fat soluble vitamins and What does their absorption depend on...
Fed
APC on chromosome 5
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

4. What are the complications/signs of familial hypercholesterolemia
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Von hippel lindau - 3

5. What happens in a B12 def
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
MRNA - tRNA
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible

6. How does cytosine become uracil
Deamination
Elastase - inhibited by alpha1 antitrypsin
40 - 60 - 80
NADH - NADPH - FADH2

7. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Alpha1 antitrypsin
Karyotyping

8. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Cre - lox system
CAG
Glucose - 2Pi - 2ADP - 2NAD+
Stored ATP - creatine phosphate - anaerobic glycolysis

9. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
F16BP
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Marfans

10. Give an example of a mitochondrial inherited disease
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Oxidized hemoglobin precipiated within RBCs
Breaks down acyl - coa to acetyl coa groups in mito

11. What defects characterize DiGeorge syndrome
Inc vit B6
Thymic - parathyroid and cardiac
Phenytoin - MTX - and sulfonamides
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan

12. What leads to the deletion of the dystrophin gene in duchenne's muscular dystrophy
X linked frame shif mutation
GAA
PMNs
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

13. What are the two possible causes of albinism
AR
Acetyl - CoA carboxylase (ACC)
Adenosine to inosine
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells

14. What does Ehlers Danlos cause and why
B-100 - CII and E
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
African Americans and Asians
Consesus sequenec of base pairs

15. Which are the acidic amino acids
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Malonyl coa
Asp and Glu

16. What is the purpose of the HMP shunt
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Pseudomonas and s aureus
Orotate precursor - with PRPP added later
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA

17. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Mediates extra remnant take up
Sucrose = glucose + fructose - lactose = glucose + galactose
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
NAD+

18. What is the main source of folate
Foliage - small reserve in liver - eat green leaves
Catabolic processes to carry reducing equivalents away as NADH
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Flank pain - hematuria - HTN - progressive renal failure

19. what findings are associated with marfans
Catabolic processes to carry reducing equivalents away as NADH
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Inc vit B6
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)

20. Mild Hurlurs + aggressive behavior no corneal clouding
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Degredation of dietary TG in small intestine
Malonyl coa
Polycystic liver disease - berry aneurysm - mitral valve prolapse

21. What are possilbe presentation for galactokinase def
Griseofulvin
Wobble
Failure to track objects or develop a social smile
Achondroplasia

22. In which state is PFK-2 active
4 under the floor
N to C
Autosomal recessive diseases
Fed

23. In which single strand DNA repair mechanism do specific endonucleases release the oligonucTIDE containing bases and DNA poly and ligase fill and reseal - and what disease occures when this is mutated
NF2 on chromosome 22
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
They yield only acetyl - CoA equivalents

24. What does lactase deficiency cause
Oral uridine administration
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Acetyl - CoA to malonyl - CoA (2C to 3C)
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

25. FAP is due to deletion On what gene On what chromosome
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
APC on chromosome 5
BOne

26. What is the function and name of vit B6
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Proton gradient

27. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
Ketone - methyl
Acetyl - CoA
Glycogen phosphorylase
NAD+

28. What is the result of vit B5 def
Vit K antagonist
Mediates chylomicron secretion
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Dermatitis - enteritis - alopecia - adrenal insuff

29. What are the 3 AR forms of homocystinuria
Disorder of aromatic amino acid metabolism
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
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
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)

30. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Specific glycosylases - AP endonuclease
Poly A polymerase - signal is AAUAA
ATP

31. What happens in zinc def
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
30 - 50 - 70
TTP
Hereditary spherocytosis

32. How do fluoroquinolones work
Defect in fibrillin
Phenylketones in urine
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Microarrays

33. Why does alpha amanitin cause liver failure and Where is it found
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Phosphorylation - glycosylation - hydroxylation
Inhibits RNA polymerase II - found in death cap mushrooms
PCR - denaturation - annealing - elongation

34. characterize mitochondrial inheritance
Transmitted only through mother - all offspring of affected females may show signs of disease
TRNA
PMNs
Met - val - arg his

35. What is the fxn of vit D
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Tyrosine
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
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

36. What enzyme adds Cl - to the H202 to makes bleach
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Myeloperoxidase
Foliage - small reserve in liver - eat green leaves
Base + ribose + phosphate (3' -5') phosphodiester bond

37. trinucleotide repeat for huntingtons
In ER - glucose 6- P to glucose
CAG
SnRNPs
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

38. What is the most abundant type of RNA
RRNA
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Q -
Pyruvate to oxaloacetate (3C to 4C)

39. What is Gowers maneuver
Assistance of upper extremities to stand up
MRNA
Kwashiorkor - small child with swollen belly
LDL

40. In eukaryotes - What does RNA poly III make
Silencers
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Niacin - constituent of NAD and NADP - derived from tryptophan
TRNA

41. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Sucrose = glucose + fructose - lactose = glucose + galactose
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Liver and leafy veggies
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

42. What is the complication of cystinuria
B12 and folate
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Mutated dystrophin gene - less severe - adolescence
Histidine

43. What is the Name and fxn of vit B5
BOne
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Liver - ovaries - seminal vesicles

44. What is the longest time of RNA and shortest
Hypoxanthine to xanthing and xanthine to uric acid
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
MRNA - tRNA
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

45. What is the RDE of the HMP shunt
Glutamate
RRNA
Glucose 6 phosphate dehydrogenase (G6PD)
Core proteins

46. What does DNA ligase do
AR
Protein kinase A
Seals.
X linked frame shif mutation

47. What is the amino acid precuror for creatine - urea and nitric oxide
Arginine
Protective against malaria
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

48. What is used to diagnose muscular dystrophies
Sucrose = glucose + fructose - lactose = glucose + galactose
Anabolic processes as a supply of reducing equivalents
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Inc CPK and muscle biopsy

49. What is a missense mutation
ATP
Changed AA (convservative - new AA is similar in chemical structure)
Diphyllobothrium latum
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA

50. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
B12 and folate
Alpha - ketoglutarate dehydrogenase complex
Karyotyping
Essential fructosuria - fructokinase AR