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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 metabolic rxns occur in the mitochondria
Neural tube
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Palate - facial and cardiac defects
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

2. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Rotenone - CN- - antimycin A - CO
Inc melt - dec fluidity
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

3. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Fibrofatty replacement of muscle - cardiac myopathy
Blood - bone marrown - amniotic fluid - placental tissue
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Krabbes - galactocerebrosidase - galactocerebroside - AR

4. What collagen type is most frequently affected in ehlers danlos and What are common complications
GAA
Neither of 2 alleles is dominant - blood groups
III - joint dislocation - anuerysms - organ rupture
PCR - denaturation - annealing - elongation

5. What is the initial transcript called and What is the capped and tailed transcript called
Phenytoin - MTX - and sulfonamides
Binds to LDL receptor - mediates VLDL secretion
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA

6. What does the golgi add to serine and threonine residues
B100 and E
17 - 17 letters in von Recklinghausen
L form
O- oligosaccharaides

7. What does apoCII do
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Adds 2 carbon with the help of biotin
Scrutinizes - hydrolyzes the bond
Cofactor for LPL

8. What co - factors are required for the pyruvated dehydrogenase complex
Dec DNA - dec lymphos leads to SCID
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Change resulting in early stop codon
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR

9. hepatosplenomegaly - aseptic necrosis of femur - bone crisis - MACS that look like crumpled tissue paper

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10. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Chylomicrons
Glycine
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Achondroplasia

11. What happens in vit D excess
Sucrose = glucose + fructose - lactose = glucose + galactose
Dec DNA - dec lymphos leads to SCID
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

12. What are the glucogenic/ketogenic amino acids
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Ile - phe - thr - trp
ADPKD
Karyotyping

13. What is incomplete penetrence and give an example
Read from a fixed starting point as a continuous sequence of bases
Mediates chylomicron secretion
Not all individuals with a mutant genotype show the mutant phenotype
Skin

14. What can vit B3 be used to treat
Hyperlipidemia
Phenytoin - MTX - and sulfonamides
Acetyl - CoA carboxylase (ACC)
Inc dicarboxylic acids - dec in glucose and ketones

15. What do neurofilaments stain for
Neurons
Carbomoyl phosphate synthetase II
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
X- linked recessive

16. characterize mitochondrial inheritance
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Transmitted only through mother - all offspring of affected females may show signs of disease
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

17. What does hepatic TG lipase do
Unwinds DNA template at replcation fork
Degradation of TG remaining in IDL
P+q = 1
Pyruvate - NAD+ - CoA

18. Pts with albinism are at inc risk For what cancer
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Leu - lys
Stop codon is recognized by release factor - and completed protein is released from ribosome
Skin

19. What does acetyl - CoA become before becoming palmitate
B100
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

20. What is the main source of folate
Prevent strands from reannealing
Kidney - ears - eyes
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
Foliage - small reserve in liver - eat green leaves

21. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
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
Removes phosphate group from substrate
Marfans
B6

22. What does the primary transcript combine with to form the spliceosome
Transmitted only through mother - all offspring of affected females may show signs of disease
Proline and lysine - vit C
SnRNPs and other proteins
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

23. What are the purely ketogenic amino acids
Alanine
Glucose -6 phosphate
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Leu - lys

24. RNA poly can't proofread - but What can it do
Chylomicrons
Initiate chains
5' to 3'
CG- 3 > AT-2 - More CG content - melting point goes up

25. What enzymes metabolize fatty acids and amino acids
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Nonsense > missense > silent
Acetoacetate and beta hydroxybutyrate
Skin

26. Which cells are rich in smooth ER
ATP - citrate
Ile - phe - thr - trp
Liver hepatocytes and steroid producing cells of the adrenal cortex
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

27. What happens in hyperammonemia
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Alpha and beta tubulin - dimers have two GTP bound
Chylomicrons

28. Type IV BM
4 under the floor
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Inhibits 50S peptidyltransferase
Tuberous sclerosis

29. 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
G6PD
Glycine - aspartate - glutamine
Hypoglycemia

30. What is the RDE of TCA cycle
N to C
Neurons
Isocitrate dehydrogenase
Inhibits RNA polymerase II - found in death cap mushrooms

31. Where are FADH2 electrons transferred to...
After citruline
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Glycogen synthase
Comlex II

32. Type I collagen
Glucose 6 phosphatase
Wobble
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

33. What inhibits pyruvate kinase
ATP and alanine
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
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
Neurofibromatosis type 1 (von Recklinghausens disease)

34. What shape does the RNA generate during splicing and why?
Glycogen phosphorylase
Liver - ovaries - seminal vesicles
Lariat shape in order and remove intron precisely and join 2 exons
Flank pain - hematuria - HTN - progressive renal failure

35. What two enzymes are involved in EtOH metabolism
EtOH dehydrogenase and acetaldehyde dehydrogenase
Glucose 6 phosphatase
No
Grows slowly - collapses quickly

36. How does abetalipoproteinemia present and What is the defect
ATP
Ketone - methyl
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
B100 and E

37. What substance inside the cell reduces glutatione
Inc insulin - dec cAMP - dec PKA
UGA - UAA and UAG
NADPH
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

38. Give an example of a mitochondrial inherited disease
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Stored ATP - creatine phosphate - anaerobic glycolysis
Failure to track objects or develop a social smile

39. Where do you find elastin and What does it do
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Cre - lox system
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.

40. Accurate base pairing is required only in the first two nucleotide positions of an mRNA codon - so conds differeing in the 3rd position may code for the same tRNA/AA due to degenerate genetic code
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Locus heterogeneity - ocular albinism is x- linked recessive
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Wobble

41. What is linkage disequilibrium
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
HDL
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

42. What clotting factors require vit K
Conversion of NE to epi
Alpha - ketoglutarate dehydrogenase complex
Arg and his inc in histones Which bind negatively charged DNA
II - VII - IX - X (1972) protein C and S

43. FAP is due to deletion On what gene On what chromosome
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Rb and p53
APC on chromosome 5
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

44. What are pyrimidines made from
9+2 arrangement of microtubules
Neg to pos
Fed
Orotate precursor - with PRPP added later

45. What is the RDE of de novo pyrimidine synthesis
Pyruvate to oxaloacetate (3C to 4C)
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Carbomoyl phosphate synthetase II
GTP

46. What does osteogenesis imperfecta causes and why
Cartilage - hyaline - vitreous body - nucleus pulposus
Von Gierke's - Pompe - Cori - McArdle
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE
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

47. What does a phosphorylase do
Wobble
Fed
Adds an inorganic phosphate onto substrate without using ATP
Heterochromatin = HighlyCondensed

48. What are the results of unbalanced translocation
75 to 90 - cloverleaf
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Ile - phe - thr - trp

49. What causes Hartnup's disease
P+q = 1
CarTWOlage
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Transmitted through both parents - affected mother may have affected children - affected father will have affected children

50. What is the defectin IV - hypertriglyceridemia
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
ATP and methionine
Fed