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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 part of the pre mRNA contains the actual genetic information coding for protein
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Activates LCAT
ATP and methionine
Exons

2. What is the RDE of gluconeogenesis
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Makes RNA primer on which DNA poly III can initiate replication
Wernicke - korsakoff - dry and wet beriberi
Fructose 1 -6 bisphosphate

3. Where is hexokinase found - What is its Km and Vmax and what uninduces it
B12 and folate
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

4. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
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
IDL
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR

5. What are the 4 assumption of the Hardy Weinberg law
CAG
RER
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Proton gradient

6. What two cells are particularly rich in RER
Mucus secreting globlet cells and antibody secreting plasma cells
APC on chromosome 5
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Mediates chylomicron secretion

7. What does helicase do
Unwinds DNA template at replcation fork
Each codon specifies only 1 amino acid
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Fructose 1 -6 bisphosphate

8. What causes Marfan syndrome
Defect in fibrillin
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Phenylethamolamine N methyl transferase

9. What does hepatic TG lipase do
2 rings
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Degradation of TG remaining in IDL
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies

10. What converts NE to epi
MRNA
Phenylethamolamine N methyl transferase
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Glutamate

11. What is DNA cloning and How do you do it?
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin
Neimann - pick - sphingomyelinase - sphingomyelin - AR
By inhibiting formation of the initiation complex and cause misreading of mRNA
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

12. What tissues have both enzymes of sorbitol metabolism
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
Phosphofructokinase 1
Stop codon is recognized by release factor - and completed protein is released from ribosome
Liver - ovaries - seminal vesicles

13. Type I collagen
Cytosol - F 1 -6 BP to fructose 6 Phosphate
2 rings
Robertsonian translocation and mosaicism
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

14. What drugs can cause folate def
GAA
Phenytoin - MTX - and sulfonamides
40 - 60 - 80
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

15. How many ATP are produced by anearobic glycolysis per molecule of glucose
Robertsonian translocation and mosaicism
Seals.
Two
5' to 3'

16. When are glycogen reserves depleted
Exercise: inc NAD/NADH - inc ADP - inc Ca
After day 1
Failure to track objects or develop a social smile
Phenylethamolamine N methyl transferase

17. What is the activated carrier for electrons
Cleft palate - cardiac abnl - pregs test
NADH - NADPH - FADH2
Metanephrine
Microtubules

18. How does patients present with ADPKD
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Flank pain - hematuria - HTN - progressive renal failure
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

19. How does warfarin work
Vit K antagonist
Essential fructosuria - fructokinase AR
III - joint dislocation - anuerysms - organ rupture
Mutated dystrophin gene - less severe - adolescence

20. What does the addition of mannose -6 phosphate do
Ca/calmodulin in muscle to coordinate with muscle activity
Connective tissue
Targets the proteins for lysosome
Nine

21. If two alleles are present - but the active allele is deleted - what happens
Disease
Nine
Makes RNA primer on which DNA poly III can initiate replication
Krabbes - galactocerebrosidase - galactocerebroside - AR

22. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
Cyclin dependent kinases;constitutive and inactive
CAG - 4
Site of steroid synthesis and detoxification of drugs and poisons
Defect in fibrillin

23. What is the defect in fructose intolerance and What does it cause
CG- 3 > AT-2 - More CG content - melting point goes up
Change resulting in early stop codon
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Conversion of NE to epi

24. How do macrolides and clindamycin work
Kidney - ears - eyes
Heterochromatin = HighlyCondensed
Binds 50S - blocking translocation
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets

25. What are the results of CF on male fertility
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Males are infertile due to bilateral absence of vas deferens
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

26. What amino acid makes up most of the octamer
Tyrosine
CTG
NAD+
Lysine and arginine

27. What is the Hardy Weinberg disease prevalence equation
P2 +2pq+ = 1
Phenylketones in urine
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Same AA - often base change in 3rd position of codon (tRNA wobble)

28. What is the defect in I- hyperchylomicronemia
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Acetyl - CoA carboxylase (ACC)
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

29. What is incomplete penetrence and give an example
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Not all individuals with a mutant genotype show the mutant phenotype
Mitochondria

30. How many nucTIDEs is a tRNA and What does the secondary sturcture form
75 to 90 - cloverleaf
Purines= A - G pyrimidine = C - T (U)
Colchicine
CAG - 4

31. What CETP do
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Terminal regions - tropocollagen
Neuralgia
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

32. What does a carboxylase do
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Oxalacetate
Adds 2 carbon with the help of biotin
Alpha - ketoglutarate dehydrogenase complex

33. Which direction does dynein go
PFK - rate limiting enzyme
Post to neg
Acetyl - CoA to malonyl - CoA (2C to 3C)
Attachment of ubiquitin to defective proteins tag them for breakdown

34. Type II cartilage
HMP shunt
17 - 17 letters in von Recklinghausen
Oxidized hemoglobin precipiated within RBCs
CarTWOlage

35. How does ethanol induce hypoglycemia
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
Fibrofatty replacement of muscle - cardiac myopathy
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

36. congenital deficiency of homogentisic acid oxidase in the degradative pathway of tyrosine to fumarate leading to dark connective tissue - brown pigmented sclera - urine turns black on standing - dz and worst complication
Alkaptonuria - may have debiliating arthralgias
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Rb and p53
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

37. What substances directly inhibit electron transport chain
Inc permeability of membrane causing a dec in proton gradient and inc in O2 consumption - ATP synthesis stops - but electron transport continues to produce heat
Disorder of aromatic amino acid metabolism
Rotenone - CN- - antimycin A - CO
Disease

38. What is the Name and fxn of vit B5
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Liver - also in kidney and gut epithelium
FISH
Infection - free radicals generated by inflammatory response

39. What is the smallest mutation a mircoarray can detect
Nonsense > missense > silent
SNP
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

40. What co - factors are required for the pyruvated dehydrogenase complex
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Orotic acid to UMP
Thymic - parathyroid and cardiac
Protein

41. How do odd chain fatty acids participate in gluconeogenesis
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
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
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

42. Very Poor Carbohydrate Metabolism stands for 4 of the glycogen storage diseases - What are thy

43. What does inc phenylalanine lead to...
Disorder of aromatic amino acid metabolism
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Phenylketones in urine
Phenylethamolamine N methyl transferase

44. Fluorescent DNA or RNA probe binds to specific gene of interest - used for specific localization of genes and direct visualization of anomalies - like microdeletions - at molecular level
FISH
Pseudomonas and s aureus
Exercise: inc NAD/NADH - inc ADP - inc Ca
Each codon specifies only 1 amino acid

45. How many rings do purines have
Heterochromatin = HighlyCondensed
Inc Cl - in sweat
Liver and leafy veggies
2 rings

46. What is mosaicism and give an example
Rotenone - CN- - antimycin A - CO
TRNA
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females

47. What are the clinical features of I cell diesase
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Alanine
FAP
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

48. Which cells are rich in smooth ER
Liver hepatocytes and steroid producing cells of the adrenal cortex
Cytosol
Microtubules
Adds 2 carbon with the help of biotin

49. What are the glucogenic/ketogenic amino acids
Neg to pos
Ile - phe - thr - trp
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
O- oligosaccharaides

50. What does osteogenesis imperfecta causes and why
Transmitted only through mother - all offspring of affected females may show signs of disease
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Mitochondria
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin