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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. 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
Glycine - aspartate - glutamine
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
HMG- CoA (HMG- CoA to mevalonate

2. What enzyme def can cause emphysema
Heterochromatin = HighlyCondensed
HDL
Alpha1 antitrypsin
Foliage - small reserve in liver - eat green leaves

3. What causes B12 def
CFTR gene - 7 - Phe 508
Griseofulvin
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year

4. What step of uric acid synthesis does xanthine oxidase catalyze
Acetyl - CoA carboxylase (ACC)
Hypoxanthine to xanthing and xanthine to uric acid
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
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

5. This is the site where negative regulators bind
Unwinds DNA template at replcation fork
Glycine - aspartate - glutamine
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Silencers

6. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Males are infertile due to bilateral absence of vas deferens
Dec DNA - dec lymphos leads to SCID
Inc vit B6
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

7. What are the 3 AR forms of homocystinuria
Males are infertile due to bilateral absence of vas deferens
IMP precursor
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol

8. Which are the basic amino acids
Locus heterogeneity - ocular albinism is x- linked recessive
Polyneuritis - symmetrical muscle wasting
RER
Arg - lys - his - arg is most basic - has has no charge at body pH

9. What converts tyrosine to DOPA
Tryosine hydroxylase
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
Cri du chat
Glucose -6 phosphate

10. Which RNA poly opens DNA at promotor site
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
X linked frame shif mutation
RNA poly II
75 to 90 - cloverleaf

11. What does vit E def cause
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Dermatitis - enteritis - alopecia - adrenal insuff
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

12. Who typically has lactase def
Glycogen phosphorylase
African Americans and Asians
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Acetly- CoA - CO2 - NADH

13. What is the defectin IV - hypertriglyceridemia
They yield only acetyl - CoA equivalents
Microtubules
RNA
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

14. What is RNAi used for
Terminal regions - tropocollagen
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
DsRNA promotes degradation of target mRNA knocking down gene expression
Palate - facial and cardiac defects

15. What produces NADPH
B12 and folate
HMP shunt
Pyruvate - NAD+ - CoA
Mitochondria

16. What regulates whether FBPase -2 or PFK-2 is active
75 to 90 - cloverleaf
Protein kinase A
CGG
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

17. What enzyme degrades a small amount of glycogen in lysosomes
Alpha 1 -4 glucosidase
Phosphorylation - glycosylation - hydroxylation
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Antibiotic use or excessive ingestion of raw eggs

18. central and peripheral demyelination with ataxia and dementia
B6
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

19. Mild Hurlurs + aggressive behavior no corneal clouding
Adds an inorganic phosphate onto substrate without using ATP
Huntingtons
Unmethylated - newly synthesized - HNPCC
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR

20. deletion of VHL gene on chromosome 3 leading to hemangioblastomas of retina/cerebellum/medulla bilateral RCC - dz and overexpression product
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Von hippel lindau - 3
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
The triphosphate bond

21. What are the two possible causes of albinism
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway

22. What is the RDE of gluconeogenesis
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Kidney - ears - eyes
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Fructose 1 -6 bisphosphate

23. What is the mutation in beckers muscular dystrophy - What is the severity and time of onset
Inc Cl - in sweat
P+q = 1
Mutated dystrophin gene - less severe - adolescence
Fructose 1 -6 bisphosphate

24. How does chloramphenicol work
Inhibits 50S peptidyltransferase
B-100 - CII and E
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Creat a nick in the helix to relieave supercoils created during replication

25. In what cells do the respiratory burst occur
PMNs
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Degredation of dietary TG in small intestine
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase

26. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Oxidative and nonoxidative - no ATP produced or used
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Skin
L form

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

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28. What is the activated carrier for electrons
RRNA
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
NADH - NADPH - FADH2

29. What are the glucogenic essential amino acids
Met - val - arg his
Conversion of NE to epi
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Liver - also in kidney and gut epithelium

30. What are the findings in Lesch - Nyhan
No - its non homologous
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
B100 and E

31. What makes up a nucleotide

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32. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
B-100 - CII and E
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Type II

33. What does arsenic do and What are th results of poisoning
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Autosomal recessive diseases
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

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

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35. What is the defect in II A familial hypercholesterolemia
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Proton gradient
DTMP
Fructose 1 -6 bisphosphate

36. What happens in folate def
UGA - UAA and UAG
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Flagella - cilia - mitotic spindles

37. What is heteroplasmy
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Initiate chains
Y shaped region along the DNA template where leading nad lagging strands are synthesized

38. trinucleotide repeat fo myotonic dystrophy
Inhibits RNA polymerase II - found in death cap mushrooms
CTG
Glutamine PRPP amidotransferase
Glycogen synthase

39. What does apoCII do
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
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
Glucose -6 phosphate
Cofactor for LPL

40. What is a frame shift
Scrutinizes - hydrolyzes the bond
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
RRNA
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

41. What is the RDE of the urea cycle
Acetly- CoA - CO2 - NADH
Carbomoyl phosphate synthetase I
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Inc intestinal absorption fo calcium and phosphate - inc bone resorption

42. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
CAG - 4
ATP hyrdolysis couple to energetically unfavorable rxns
Modifies N- oligosaccharides
Adds 2 carbon with the help of biotin

43. What happens with wet beriberi
High output cardiac failure - dilated cardiomyopathy - edema
Type II
Glutamine PRPP amidotransferase
VLDL

44. What is the target of the 3' hydroxyl attack
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
The triphosphate bond
Degredation of dietary TG in small intestine
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 fat soluble vitamins and What does their absorption depend on...
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
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
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

46. What are the only purely ketogenic amino acids
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Oligomycin
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Lysine and leucine

47. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Flank pain - hematuria - HTN - progressive renal failure
Base + ribose + phosphate (3' -5') phosphodiester bond
Promotor - TATA box - and CAAT box - AT rich
MEN - 2A and 2B with ret gene

48. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Inc melt - dec fluidity

49. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Methionine encode by only 1 codon (AUG)
Glycogen synthase
FAP
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

50. What does a phosphorylase do
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
After citruline
9+2 arrangement of microtubules
Adds an inorganic phosphate onto substrate without using ATP