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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 are the irreversible enzymes of gluconeogenesis
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Robertsonian translocation and mosaicism
Neg to pos
Paclitaxel

2. What is the activated carrier for methyl groups
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Inhibit DNA gyrase specific for prokaryotic topoisomerase
RER
SAM

3. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Catabolic processes to carry reducing equivalents away as NADH
DNA
Dermatitis - glossitis - and diarrhea
Sucrose = glucose + fructose - lactose = glucose + galactose

4. What is the prevalence of an X- linked recessive disease in males and in females
Glutamine PRPP amidotransferase
Type II
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
Q -

5. What is the amino acid precuros for niacin and serotonin/melatonin
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Modifies N- oligosaccharides
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Tryptophan

6. What is Retin A used topically for
Wrinkles and acne
1 kind with multiple subunits
Intermediate filaments
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

7. What does glycosylation of pro alpha chian yield and What is the structure
LCAT (lecithin cholesterol acyltransferase)
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
Procollagen - triple helix of 3 alpha collagen chains
Stored ATP - creatine phosphate - anaerobic glycolysis

8. What converts DOPA to dopamine
Dopa decarboxylase
Glycolysis and aerobic respiration
Accelearted muscle breakdown
Inhibits the Na/K pump by binding the K side

9. What chromosome is the NF gene on...
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Pyruvate - NAD+ - CoA
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
17 - 17 letters in von Recklinghausen

10. What is the most abundant protein in the body
Thymic - parathyroid and cardiac
Exons
Collagen
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

11. What are the findings in orotic aciduria
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive

12. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
Grows slowly - collapses quickly
Tuberous sclerosis
Intermediate filaments
Paclitaxel

13. What enzyme degrades a small amount of glycogen in lysosomes
Alpha 1 -4 glucosidase
Deamination
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
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

14. 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)
Removes phosphate group from substrate
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
PCR - denaturation - annealing - elongation

15. What is the active form of vit D
1 -25 OH2 D3 = calcitriol
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Base + ribose
Wernicke - korsakoff - dry and wet beriberi

16. In which state is FBPase -2 active
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Fasting
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
Histidine

17. What stretch of DNA that alters gene expression by binding of transcription factors
GAA
Basement membrane or basal lamina
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Enhancers

18. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
SnRNPs
Fibroblast
Change resulting in early stop codon
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects

19. What do neurofilaments stain for
Glycogen phosphorylase
Neurons
40 - 60 - 80
Carnitine acyltransferase I

20. characterize mitochondrial inheritance
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Neurofibromatosis type 1 (von Recklinghausens disease)
Dec methionine - inc cystiene - inc B12/folate
Transmitted only through mother - all offspring of affected females may show signs of disease

21. What happens do glycogen in skeletal muscle during exercise
Liver hepatocytes and steroid producing cells of the adrenal cortex
MRNA
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Glycogenolysis to form glucose

22. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Marfans
Inhibits the Na/K pump by binding the K side
Alpha - ketoglutarate dehydrogenase complex

23. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Williams syndrome
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Huntingtons
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

24. What does degenerate/rundant genetic code refer to...
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
HMP shunt
More than 1 codon may code for the same amino acid
Active secretion in lungs and GI - reabsorbs in skin

25. What is the results of vit B1 def
X- linked recessive
Acetyl - CoA
P+q = 1
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

26. How is orotic aciduria inherited
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
AR
Mutated dystrophin gene - less severe - adolescence
Specific glycosylases - AP endonuclease

27. What enzyme esterifies 2/3 of plasma cholesterol
Oxidized hemoglobin precipiated within RBCs
FAP
LCAT (lecithin cholesterol acyltransferase)
Core proteins

28. How is Lesch Neyhan inherited
HMG- CoA synthase
X- linked recessive
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Nissl body - enzyme and NTs

29. In eukaryotes - What does RNA poly I make
CGG
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
RRNA
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

30. What is the defect in I- hyperchylomicronemia
Acetyl - CoA carboxylase (ACC)
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
X- linked recessive

31. What are the mRNA stop codons
Antioxidant - protects RBCs and membrances from free radical damage
Neimann - pick - sphingomyelinase - sphingomyelin - AR
UGA - UAA and UAG
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

32. What is dominant negative mutation and give an example
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Achondroplasia
After citruline
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

33. What defects characterize velocardiofacial syndrome
Palate - facial and cardiac defects
African Americans and Asians
NADH - NADPH - FADH2
Grows slowly - collapses quickly

34. What happens in vit B2 def
Cleft palate - cardiac abnl - pregs test
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Antibiotic use or excessive ingestion of raw eggs

35. What is axonemal dynein
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Disease
Chylomicrons

36. What are the glucogenic/ketogenic amino acids
Griseofulvin
Ile - phe - thr - trp
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

37. What is kartageners syndrome
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Dermatitis - alopecia - enteritis
Neurons

38. What is DNA cloning and How do you do it?
APRT + PRPP
Histidine
Proton gradient
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

39. What does DNA poly I do?
PMNs
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
4 under the floor
APKD1 on chromosome 16

40. Describe the structure of cilia
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Exercise: inc NAD/NADH - inc ADP - inc Ca
Cri du chat
9+2 arrangement of microtubules

41. Which anti breast cancer drugs work on micortubules
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
MRNA
Changed AA (convservative - new AA is similar in chemical structure)
Paclitaxel

42. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Chylomicrons
2pq
Anabolic processes as a supply of reducing equivalents

43. What does the CFTR channel do in the lungs - GI tract and skin
Active secretion in lungs and GI - reabsorbs in skin
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Vit K antagonist
Tuberous sclerosis

44. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
Inc glucagon - inc cAMP - inc PKA
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Heterochromatin = HighlyCondensed
Removal of N or C termal propeptides from zymogens to generate mature proteins

45. Where are cytosolic and organellar proteins made
Phenylalanine
Free ribosomes
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Neither of 2 alleles is dominant - blood groups

46. What is the source of energy in the fasting state between meals
Sulfation
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Adds an inorganic phosphate onto substrate without using ATP
Basement membrane or basal lamina

47. What rxn does propionyl - CoA carboxylase catalyze
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
CGG
NF2 on chromosome 22

48. nucleotide repeat for fredreich's ataxia
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
GAA
Glycine - aspartate - glutamine
GTP

49. How is ammonium transported from muscle to the liver for urea cycle
Attachment of ubiquitin to defective proteins tag them for breakdown
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
Tryptophan
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

50. What is the Name and function of vit B2
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Glycine - aspartate - glutamine
Cytosol
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation