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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. How is ATP used by the cell
ATP hyrdolysis couple to energetically unfavorable rxns
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Disorder of aromatic amino acid metabolism
Autosomal recessive diseases

2. What is the longest time of RNA and shortest
LCAT (lecithin cholesterol acyltransferase)
ADPKD
MRNA - tRNA
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond

3. What does an umabiguous genetic code refer to...
Q -
Each codon specifies only 1 amino acid
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Y shaped region along the DNA template where leading nad lagging strands are synthesized

4. What does Alports syndrome cause and why
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Inc CPK and muscle biopsy
Neurofibromatosis type 1 (von Recklinghausens disease)

5. What does apoB48 do
Glutamine PRPP amidotransferase
Muscle
Mediates chylomicron secretion
Same as sprint + OXPHOS

6. What defects characterize DiGeorge syndrome
5' to 3'
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Thymic - parathyroid and cardiac
Exercise: inc NAD/NADH - inc ADP - inc Ca

7. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
Alkaptonuria - may have debiliating arthralgias
Wobble
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Zero

8. What is the purpose of the HMP shunt
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Familial hypercholesterolemia - hyperlipidemia type IIA
Alpha 1 -6 and alpha 1 -4

9. What kind of branches do glycogen branches have
Griseofulvin
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Terminal regions - tropocollagen
Alpha 1 -6 and alpha 1 -4

10. Acetyl - CoA carboxylase catalyzes what rxn
Hyperlipidemia
Acetyl - CoA to malonyl - CoA (2C to 3C)
Carnitine shuttle - acyl - coa from cyto to mito
Familial hypercholesterolemia - hyperlipidemia type IIA

11. What are the blood glucose levels maintained by for days 1-3
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)
Males are infertile due to bilateral absence of vas deferens
In ER - glucose 6- P to glucose
HMG- CoA synthase

12. What is the most abundant protein in the body
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Collagen
Mcardle's - skeletal muscle glycogen posphorylase
Schwann cells - lens - retina - kidneys

13. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Neg to pos
Failure to track objects or develop a social smile

14. Which step in the de novo purine and pyrimidine synthesis pathway requires just aspartate
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Orotic acid to UMP
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
Binds to LDL receptor - mediates VLDL secretion

15. What apolipoprotein is on LDL
Abnormal protein folding - degradation before reaching cell surface
Sulfation
B100
IMP precursor

16. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Dec DNA - dec lymphos leads to SCID
2 -4 DNP - aspirin
N to C

17. What are the teratogenic effects of vit A and What test must be ordered before starting a woman on isotreitinoin for severe acne
CG- 3 > AT-2 - More CG content - melting point goes up
Proton gradient
IMP precursor
Cleft palate - cardiac abnl - pregs test

18. What part of the pre mRNA contains the actual genetic information coding for protein
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Inc dicarboxylic acids - dec in glucose and ketones
30 - 50 - 70
Exons

19. What shape does the RNA generate during splicing and why?
Lariat shape in order and remove intron precisely and join 2 exons
Only processed RNA
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase

20. What is the physiologic role of dystrophin
Not all individuals with a mutant genotype show the mutant phenotype
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Inc Cl - in sweat
Alpha 1 -6 and alpha 1 -4

21. What is the Name and fxn of vit B5
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Collagen
Phenylalanine hydroxylase
SnRNPs and other proteins

22. What step begins the urea cycle and What is the enzyme needed - Where does it happen
Intermediate filaments
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Two
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

23. What is imprinting and give an example

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24. Describe robertsonian translocation
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Pseudomonas and s aureus
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

25. What are the two transgenic strategies in mice
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

26. What does helicase do
Unwinds DNA template at replcation fork
Protective against malaria
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Creat a nick in the helix to relieave supercoils created during replication

27. What causes Edwards syndrome and What is it
Anabolic processes as a supply of reducing equivalents
THFs
Q -
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year

28. What does desmin stain for
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Silencers
Muscle
Inc dicarboxylic acids - dec in glucose and ketones

29. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Type II
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
MEN - 2A and 2B with ret gene

30. What does CATCH 22 stand for and What causes is...
Infection - free radicals generated by inflammatory response
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21

31. In prokaryotes - What does makes the different types of RNA
1 kind with multiple subunits
Fibrofatty replacement of muscle - cardiac myopathy
Polyneuritis - symmetrical muscle wasting
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

32. What produces NADPH
Cartilage - hyaline - vitreous body - nucleus pulposus
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
HMP shunt
Glycine - aspartate - glutamine

33. What is a silent mutation
Fibrofatty replacement of muscle - cardiac myopathy
Glycine - aspartate - glutamine
Neurofibromatosis type 1 (von Recklinghausens disease)
Same AA - often base change in 3rd position of codon (tRNA wobble)

34. What is the treatment for dec affinity of cystathionine synthase for pyroxidal phosphate
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Inc vit B6

35. What kind of RNA is transported out of the nucleus
Tryptophan
Paclitaxel
Glycine - aspartate - glutamine
Only processed RNA

36. What do the single stranded binding proteins do
Must be both activated and inactivated for cell cycle to progress
Prevent strands from reannealing
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus

37. What enzyme converts phenylalanine to tyrosin
Methionine encode by only 1 codon (AUG)
Not all individuals with a mutant genotype show the mutant phenotype
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year
Phenylalanine hydroxylase

38. What enzyme def can cause emphysema
Asp and Glu
OTC has hyperammonemia - orotic aciduira does not
More than 1 codon may code for the same amino acid
Alpha1 antitrypsin

39. What does a dehydrogenase do
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Inc vit B6
Ca/calmodulin in muscle to coordinate with muscle activity
Oxidizes substrate

40. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Alpha1 antitrypsin
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
L form

41. Type I bone
BOne
2 -4 DNP - aspirin
Autosomal recessive diseases
Adds 2 carbon with the help of biotin

42. How do macrolides and clindamycin work
Binds 50S - blocking translocation
2 rings
CGG
Mucus secreting globlet cells and antibody secreting plasma cells

43. Where is glucose 6 phosphatase found and What does it do
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
In ER - glucose 6- P to glucose
Marfans
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive

44. What are the functinos of vitamin A
Glycogen phosphorylase
Inhibits RNA polymerase II - found in death cap mushrooms
B-100 - CII and E
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

45. What are the results of pancreatic insuff in CF
CarTWOlage
Malabsorption and steatorrhea (ADEK)
Glycine
Ile - phe - thr - trp

46. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
Site of steroid synthesis and detoxification of drugs and poisons
Lacks glucose 6 phophatase
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
DTMP

47. How many ATP are created by aerobic metobolism of glucose in muslce via what shuttle
Exercise: inc NAD/NADH - inc ADP - inc Ca
30 - glycerol -3- phosphate shuttle
Glycolysis and aerobic respiration
Rb and p53

48. What are the water soluble vitamins - which ones are stored
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
40 - 60 - 80
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

49. What is the function of Zinc
40 - 60 - 80
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
AMP - fructose 2 -6 BP
Isocitrate dehydrogenase

50. What step of uric acid synthesis does xanthine oxidase catalyze
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Oral uridine administration
Hypoxanthine to xanthing and xanthine to uric acid