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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. characterize autosomal domint inheritance
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
1 -25 OH2 D3 = calcitriol
Acetly- CoA - CO2 - NADH

2. recurrent pulmonary infxns in CF are due to what organisms
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Reads usual codon but inserts wrong AA
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Pseudomonas and s aureus

3. What happens in vit B2 def
Dec methionine - inc cystiene - inc B12/folate
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

4. What lab technique is use to profile gene expression levels of thousands of genes simultaneously to study certain diseases and treatments
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Catabolic processes to carry reducing equivalents away as NADH
Microarrays

5. What CETP do
2 -4 DNP - aspirin
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
By inhibiting formation of the initiation complex and cause misreading of mRNA
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies

6. What is the RDE of cholesterol synthesis
HMG- CoA reductase
Hyperlipidemia
Dermatitis - glossitis - and diarrhea
Infection - free radicals generated by inflammatory response

7. Infection with what organism can cause B12 def
Arg and his inc in histones Which bind negatively charged DNA
32 - malate aspartate shuttle
Adenosine to inosine
Diphyllobothrium latum

8. What is the longest time of RNA and shortest
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
MRNA - tRNA
75 to 90 - cloverleaf

9. What is a missense mutation
Changed AA (convservative - new AA is similar in chemical structure)
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Ribose 5- P to PRPP
Bind 30s subunit preventing attachment of aminoacyl - tRNA

10. How do stable (quiescent) cells grow and regenerate and What are examples
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
B100 and E
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes

11. deletion of VHL gene on chromosome 3 leading to hemangioblastomas of retina/cerebellum/medulla bilateral RCC - dz and overexpression product
Von hippel lindau - 3
MEN - 2A and 2B with ret gene
Citrate - acetyl coa from mito to cyto
Nonsense > missense > silent

12. Describe the structure of cilia
Malapsorption syndromes like sprue or CF or mineral oil intake
9+2 arrangement of microtubules
4 under the floor
Enhancers

13. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Epithelial cells
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Marasmus - muscle wasting
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

14. What drugs can cause folate def
Phenytoin - MTX - and sulfonamides
Disorder of aromatic amino acid metabolism
No - its non homologous
Niacin - constituent of NAD and NADP - derived from tryptophan

15. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Connective tissue
HGPRT - defective purine salvage - excess uric acid production
Protein

16. What happens do glycogen in skeletal muscle during exercise
Only processed RNA
Fibrofatty replacement of muscle - cardiac myopathy
Glycogenolysis to form glucose
Neuralgia

17. What is the TX for CF and What does it do
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Stop codon is recognized by release factor - and completed protein is released from ribosome
5' to 3'

18. Type I bone
BOne
IMP precursor
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

19. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Grows slowly - collapses quickly
Mediates extra remnant take up
Ile - phe - thr - trp
Marfans

20. What is the source of energy in the fasting state between meals
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Cartilage - hyaline - vitreous body - nucleus pulposus
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Alpha 1 -4 glucosidase

21. Pts with albinism are at inc risk For what cancer
Avidin
X linked frame shif mutation
Oxidizes substrate
Skin

22. What 3 syndromes are associated with vit B1 def
Wernicke - korsakoff - dry and wet beriberi
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
Alpha 1 -4 glucosidase
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

23. What tissues have both enzymes of sorbitol metabolism
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Liver - ovaries - seminal vesicles
APC on chromosome 5
Glycogenolysis to form glucose

24. In what cells do the respiratory burst occur
PMNs
More than 1 codon may code for the same amino acid
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
APKD1 on chromosome 16

25. What is the pathway in the fasting state leading to inc FBPase -2 and dec PFK-2
Inc glucagon - inc cAMP - inc PKA
Ribose 5- P to PRPP
Microarrays
HGPRT - defective purine salvage - excess uric acid production

26. What is the breakdown product of epi
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Metanephrine
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Mediates chylomicron secretion

27. What is incomplete penetrence and give an example
RER
Tyrosine
Not all individuals with a mutant genotype show the mutant phenotype
Cleft palate - cardiac abnl - pregs test

28. Where is vit A found in the diet
Inc melt - dec fluidity
Poly A polymerase - signal is AAUAA
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Liver and leafy veggies

29. What is the Name and fxn of vit B12
Rotenone - CN- - antimycin A - CO
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
1 ring
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

30. What is the prevalence of an X- linked recessive disease in males and in females
Facial flushing
Glycogenolysis to form glucose
Q -
Enhancers

31. decreases In what substances can cause PKU
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Protein
No
Oral uridine administration

32. What is codominance and give an example
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
No - its non homologous
Neither of 2 alleles is dominant - blood groups
Wrinkles and acne

33. Where is glucose 6 phosphatase found and What does it do
Superoxide dismutase
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
In ER - glucose 6- P to glucose
Thymic - parathyroid and cardiac

34. Where is PEP carboxykinase found - What does it do - and What does it require
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Unwinds DNA template at replcation fork
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

35. What is the defect in I- hyperchylomicronemia
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
BOne
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Glucose 6 phosphate dehydrogenase (G6PD)

36. Where are FADH2 electrons transferred to...
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Flank pain - hematuria - HTN - progressive renal failure
Comlex II
Result from phagocytic removal of heinz bodies my macs - G6PD def

37. Where is EtOH dehydrogenase located
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
TRNA
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Cytosol

38. What is chediak higashi
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Chylomicrons
CGG
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

39. characterize mitochondrial inheritance
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Transmitted only through mother - all offspring of affected females may show signs of disease
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility

40. Which RNA poly opens DNA at promotor site
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
Intermediate filaments
Inhibits RNA polymerase II - found in death cap mushrooms
RNA poly II

41. How is orotic aciduria inherited
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
APRT + PRPP
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
AR

42. What is heteroplasmy
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Acetyl - CoA
4 under the floor
Basement membrane or basal lamina

43. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Reads usual codon but inserts wrong AA
Krabbes - galactocerebrosidase - galactocerebroside - AR
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses

44. What is maternal PKU
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Blood - bone marrown - amniotic fluid - placental tissue
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

45. What happens in zinc def
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
NAD+
LCAT (lecithin cholesterol acyltransferase)
Microtubules

46. What step begins the urea cycle and What is the enzyme needed - Where does it happen
Tyrosine
Phenytoin - MTX - and sulfonamides
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

47. 1 g of protein or cabrohydrate = ?kcal
Met - val - arg his
Four
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Neural tube

48. For eukaryotes - Where does replication begin?
Consesus sequenec of base pairs
Protective against malaria
By inhibiting formation of the initiation complex and cause misreading of mRNA
Change resulting in early stop codon

49. What is the energy source in the fed state right after a meal
Alkaptonuria - may have debiliating arthralgias
HMG- CoA synthase
Glycolysis and aerobic respiration
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

50. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
Seals.
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Specific glycosylases - AP endonuclease
Oligomycin