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Biochemistry

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Answer 50 questions in 15 minutes.
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1. FAP is due to deletion On what gene On what chromosome
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Sulfation
APC on chromosome 5
N to C

2. What collagen type is most frequently affected in ehlers danlos and What are common complications
Essential fructosuria - fructokinase AR
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
III - joint dislocation - anuerysms - organ rupture
Nonsense > missense > silent

3. For eukaryotes - Where does replication begin?
Consesus sequenec of base pairs
Base + ribose + phosphate (3' -5') phosphodiester bond
Sucrose = glucose + fructose - lactose = glucose + galactose
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

4. What is the Hardy Weinberg disease prevalence equation
X- linked recessive
P2 +2pq+ = 1
B6
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

5. What rxn does propionyl - CoA carboxylase catalyze
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
APRT + PRPP
FMR1 gene - methylation - associated with chromosomal breakage
Bruton's agammaglobulinemia - wiskott - aldrich - fabrys disease - G6PD def - ocular albinism - Lesch - Nyhan syndrome - Duchenne and Becker Muscular Dystrophy - hunter's syndrome - hemophilia A and B

6. How does chloramphenicol work
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Alpha and beta tubulin - dimers have two GTP bound
Inhibits 50S peptidyltransferase

7. Which are the acidic amino acids
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
CTG
Asp and Glu
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

8. What is linkage disequilibrium
Neuralgia
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding

9. What happens in elongation of protein synthesis

10. Type I bone
Attachment of ubiquitin to defective proteins tag them for breakdown
BOne
Two
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility

11. What is the function and name of vit B6
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
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
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
NAD+

12. In a marathon Where does energy come from
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Oxidized hemoglobin precipiated within RBCs
Glycogen and FFA oxidation; glucose conserved for final sprinting

13. An inability to convert orotic acid to UMP would be caused by a deficiency either of which two enzymes

14. 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
1 kind with multiple subunits
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
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Alkaptonuria - may have debiliating arthralgias

15. What happens in hyperammonemia
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
B100 and E
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

16. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Liver hepatocytes and steroid producing cells of the adrenal cortex
Karyotyping
Grows slowly - collapses quickly
GAA

17. characterize mitochondrial inheritance
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
Lariat shape in order and remove intron precisely and join 2 exons
Not all individuals with a mutant genotype show the mutant phenotype
Transmitted only through mother - all offspring of affected females may show signs of disease

18. What does acetyl - CoA become before becoming palmitate
Hypoxanthine to xanthing and xanthine to uric acid
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

19. 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
Foliage - small reserve in liver - eat green leaves
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

20. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Mucus secreting globlet cells and antibody secreting plasma cells
Terminal regions - tropocollagen
Huntingtons
Paclitaxel

21. What is the physiologic role of dystrophin
Defect in fibrillin
Read from a fixed starting point as a continuous sequence of bases
Four
Anchor muscle fibers - primarily in skeletal and cardiac muscle

22. Of the four possible fates for pyruvate - which one carries amino groups to liver from muscle
B100 and E
IDL
Alanine
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive

23. Gene imprinting implies that How many alleles are active at a single locus
Pyruvate to oxaloacetate (3C to 4C)
HMG- CoA reductase
One
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

24. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Essential fructosuria - fructokinase AR
Neither of 2 alleles is dominant - blood groups
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate

25. Where is vit B12 found
PMNs
40 - 60 - 80
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Hypoglycemia

26. What is NAD+ generally used for
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Leu - lys
Catabolic processes to carry reducing equivalents away as NADH
Glycogen synthase

27. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Antibiotic use or excessive ingestion of raw eggs
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
MEN - 2A and 2B with ret gene
Pyruvate - NAD+ - CoA

28. What kind of RNA is transported out of the nucleus
Oligomycin
CTG
Only processed RNA
Phenylalanine

29. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Must be both activated and inactivated for cell cycle to progress

30. What does beta oxidation do and Where does it occur
Alpha - ketoglutarate dehydrogenase complex
Blood - bone marrown - amniotic fluid - placental tissue
Breaks down acyl - coa to acetyl coa groups in mito
APRT + PRPP

31. What apolipoproteins are on IDL
B100 and E
Read from a fixed starting point as a continuous sequence of bases
Microtubules
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

32. What does DNA poly III do?

33. In what cell is collagen synthesis initiated
Fibroblast
Essential fructosuria - fructokinase AR
Leu - lys
CAG - 4

34. What substance accumulates in galactokinase def and What is the clinical picture
Deamination
Glucose 6 phosphatase
Griseofulvin
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

35. Acetyl - CoA carboxylase catalyzes what rxn
Not all individuals with a mutant genotype show the mutant phenotype
MRNA
Acetyl - CoA to malonyl - CoA (2C to 3C)
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

36. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Specific glycosylases - AP endonuclease
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

37. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Fibrofatty replacement of muscle - cardiac myopathy
Antioxidant - protects RBCs and membrances from free radical damage

38. What are possilbe presentation for galactokinase def
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Failure to track objects or develop a social smile
Assistance of upper extremities to stand up
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

39. What is trimming
Removal of N or C termal propeptides from zymogens to generate mature proteins
Ketone - methyl
30 - glycerol -3- phosphate shuttle
Krabbes - galactocerebrosidase - galactocerebroside - AR

40. What happens in the first stage of collagen synthesis - and Where does it happen
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Sons of heterozygous mothers have 1/2 half chance of being affected - no male to male transmission - and often more severe in males - heterozygous females may be affected
Oxalacetate

41. What activates the pyruvate dehydrogenase complex
Exercise: inc NAD/NADH - inc ADP - inc Ca
SnRNPs and other proteins
Mucus secreting globlet cells and antibody secreting plasma cells
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

42. What liberates glucose from glucose 6 P
Glucose 6 phosphatase
Dopa decarboxylase
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly

43. In which structures do you find microtubules
Flagella - cilia - mitotic spindles
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Niacin - constituent of NAD and NADP - derived from tryptophan
Each codon specifies only 1 amino acid

44. What test is used for B12 def
Schilling test
Lysine and arginine
Rotenone - CN- - antimycin A - CO
Nissl body - enzyme and NTs

45. What does the mutation in the gene cause in protein synthesis
Failure to track objects or develop a social smile
Abnormal protein folding - degradation before reaching cell surface
Chylomicrons
Glycogen and FFA oxidation; glucose conserved for final sprinting

46. What is Retin A used topically for
Arginine
Wrinkles and acne
Phenylketones in urine
Glucose -6 phosphate

47. In which state is FBPase -2 active
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Rotenone - CN- - antimycin A - CO
Fasting
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

48. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
African Americans and Asians
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
CAG - 4
Met - val - arg his

49. What is maternal PKU
Diphyllobothrium latum
MRNA
By inhibiting formation of the initiation complex and cause misreading of mRNA
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

50. What is the amino acid precuros for niacin and serotonin/melatonin
Tryptophan
Citrate - acetyl coa from mito to cyto
Comlex II
Catabolic processes to carry reducing equivalents away as NADH