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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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This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Where is vit B12 found
Carbomoyl phosphate synthetase II
Coenzyme A - lipoamide
One
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

2. What is the most abundant type of RNA
RRNA
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Bind 30s subunit preventing attachment of aminoacyl - tRNA
RNA poly II

3. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
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
DNA
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

4. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Mcardle's - skeletal muscle glycogen posphorylase
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Particular sequence of DNA where replicatino begins - may be single of multiple
FAP

5. What does a decrease in decrease in NADPH lead to and why
Catabolic processes to carry reducing equivalents away as NADH
Orotate precursor - with PRPP added later
Fed
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

6. Where is acetaldehyde located
Mitochondria
Tryptophan
Neuralgia
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss

7. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Essential fructosuria - fructokinase AR
N to C
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Cyclin dependent kinases;constitutive and inactive

8. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Y shaped region along the DNA template where leading nad lagging strands are synthesized
CFTR gene - 7 - Phe 508
RRNA
Cytosol - F 1 -6 BP to fructose 6 Phosphate

9. telangiectasia - recrrent epistaxis - skin discolorations - AVMs
Same as sprint + OXPHOS
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Carbomoyl phosphate synthetase II
HMG- CoA synthase

10. What do B- complex vitamin deficiencies often result in
Dermatitis - glossitis - and diarrhea
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
LCAT (lecithin cholesterol acyltransferase)
Wernicke - korsakoff - dry and wet beriberi

11. Where are the secretory proteins made and N- linked oligosaccharide addtions put on proteins
RER
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA

12. What is anticipation and give an example
Lysine and leucine
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
No - its non homologous

13. What is the RDE of cholesterol synthesis
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Glucose 6 phosphatase
HMG- CoA reductase
Inc insulin - dec cAMP - dec PKA

14. What is the TX for PKU
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
CarTWOlage
By inhibiting formation of the initiation complex and cause misreading of mRNA
Protein

15. How does cytosine become uracil
Anabolic processes as a supply of reducing equivalents
LDL
Familial hypercholesterolemia - hyperlipidemia type IIA
Deamination

16. What two amino acids are required druing periods of growth and why
Cartilage - hyaline - vitreous body - nucleus pulposus
Oral uridine administration
DsRNA promotes degradation of target mRNA knocking down gene expression
Arg and his inc in histones Which bind negatively charged DNA

17. what findings are associated with marfans
NAD+
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates

18. congenital microdeletion of long arm of chromosoe 7 with findings of elfin facies - mental retardation - hypercalcemia - well developed verbal skills - extreme friendliness with strangers - cardiovascular problems
Modifies N- oligosaccharides
B100 and E
Williams syndrome
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

19. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Terminal regions - tropocollagen
Tuberous sclerosis
Anchor muscle fibers - primarily in skeletal and cardiac muscle
ATP

20. Why can't muscle produce in gluconeogenesis
ATP and alanine
Lacks glucose 6 phophatase
IDL
Fibroblast

21. What are the glucogenic/ketogenic amino acids
Abnormal protein folding - degradation before reaching cell surface
Fibroblast
Oligomycin
Ile - phe - thr - trp

22. nucleotide repeat for fragile x
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
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
CGG
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

23. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
L form
GAA
Cre - lox system
Mebendazole/thiabendazole

24. Why does alpha amanitin cause liver failure and Where is it found
Rotenone - CN- - antimycin A - CO
Inhibits RNA polymerase II - found in death cap mushrooms
UDP glucose pyrophosphorylase
Connective tissue

25. What does the deletion of the dystrophin gene lead to...
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
African Americans and Asians
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Accelearted muscle breakdown

26. In eukaryotes - What does RNA poly I make
RRNA
Foliage - small reserve in liver - eat green leaves
Medial dorsal nucleus of thalamus - mamillary bodies
SnRNPs and other proteins

27. The pyruvate dehydrogenase complex serves In what reaction: products
1 -25 OH2 D3 = calcitriol
Acetly- CoA - CO2 - NADH
5' to 3'
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations

28. What is the limiting reagent in EtOH metabolism
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Males are infertile due to bilateral absence of vas deferens
NAD+
Niacin - constituent of NAD and NADP - derived from tryptophan

29. What causes B12 def
Rotenone - CN- - antimycin A - CO
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
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

30. What enzyme becomes essential in PKU
Tyrosine
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Acetyl - CoA

31. What are the findings in Down's syndrome
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
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
Antibiotic use or excessive ingestion of raw eggs
Inc insulin - dec cAMP - dec PKA

32. What converts limit dextran to glucose
Debranching enzyme
EtOH dehydrogenase and acetaldehyde dehydrogenase
Terminal regions - tropocollagen
Only processed RNA

33. What are covalent alterations
Inc insulin - dec cAMP - dec PKA
Alpha 1 -4 glucosidase
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
Phosphorylation - glycosylation - hydroxylation

34. What converts dopamine to NE
Dopamine beta hydroxylase
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
32 - malate aspartate shuttle
1 -25 OH2 D3 = calcitriol

35. trinucleotide repeat for huntingtons
CAG
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Peroxide

36. What is the most abundant protein in the body
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
Collagen
ATP and methionine
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA

37. What does NADPH oxidase deficiency result in and why
Carnitine acyltransferase I
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
P+q = 1
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

38. Severe fasting hypoglycemia - inc glycogen storage in liver - inc blood lactate - hepatomegaly - dz and def enzyme
Oxidizes substrate
Von gierkes - glucose 6 phosphatase
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly

39. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Von hippel lindau - 3
Terminal regions - tropocollagen
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
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

40. What step of uric acid synthesis does xanthine oxidase catalyze
Hypoxanthine to xanthing and xanthine to uric acid
High output cardiac failure - dilated cardiomyopathy - edema
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Kidney - ears - eyes

41. In prokaryotes - What does makes the different types of RNA
Sulfation
1 kind with multiple subunits
Defect in fibrillin
Actin and myosin

42. Who typically has lactase def
Pyruvate - NAD+ - CoA
African Americans and Asians
CAG
HMG- CoA reductase

43. What fxn does glucokinase serve in the liver
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Degredation of dietary TG in small intestine
Procollagen - triple helix of 3 alpha collagen chains
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

44. What tissues have only aldose reductase
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
Schwann cells - lens - retina - kidneys
OTC has hyperammonemia - orotic aciduira does not
Kidney - ears - eyes

45. What initiates protein synthesis
THFs
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Nature and severity of phenotype vary from 1 individual to another - NF type 1

46. What does desmin stain for
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Muscle
Cre - lox system
Citrate - acetyl coa from mito to cyto

47. What does amino acid catabolsim results in the formation of what?
Coenzyme A - lipoamide
Each codon specifies only 1 amino acid
Mediates extra remnant take up
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

48. How is ammonium transported from muscle to the liver for urea cycle
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
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
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
Glycine - aspartate - glutamine

49. What is a frame shift
Liver and leafy veggies
Schilling test
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Dermatitis - alopecia - enteritis

50. What are the reactants for glycolysis
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Glucose - 2Pi - 2ADP - 2NAD+
APRT + PRPP
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR