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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 does glycosylation of pro alpha chian yield and What is the structure
Keep glutathione reduced so it can detoxify free radicals and peroxides
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Procollagen - triple helix of 3 alpha collagen chains
Free ribosomes

2. What catacholamine step is SAM required for
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
In ER - glucose 6- P to glucose
Conversion of NE to epi
P2 +2pq+ = 1

3. What else can phosphoylate phosphorylase kinase
Heterochromatin = HighlyCondensed
Proline and glycine (non glycosylated forms)
Ca/calmodulin in muscle to coordinate with muscle activity
TRNA

4. What causes patau's syndrome and What is it
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
Glucose 6 phosphate dehydrogenase (G6PD)
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Four

5. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Autosomal recessive diseases
B12 and folate
AMP - fructose 2 -6 BP
Microtubules

6. what happens in acyl coa dehyrdogenase def
Inc dicarboxylic acids - dec in glucose and ketones
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Polycystic liver disease - berry aneurysm - mitral valve prolapse
30 - glycerol -3- phosphate shuttle

7. What is Gowers maneuver
Assistance of upper extremities to stand up
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
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

8. What CETP do
Terminal regions - tropocollagen
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
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)

9. What does DNA poly III do?

10. What does a northern blot use as its sample
TRNA
RNA
MRNA
Glucose -6 phosphate

11. What is NAD+ generally used for
Alpha 1 -6 and alpha 1 -4
Catabolic processes to carry reducing equivalents away as NADH
Exons
Glutamate

12. Type III collagen
FMR1 gene - methylation - associated with chromosomal breakage
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Cre - lox system

13. What are pyrimidines made from
25OHD3
Vincritsine/vinblastine
Orotate precursor - with PRPP added later
SAM

14. What is the RDE of de novo pyrimidine synthesis
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Carbomoyl phosphate synthetase II
Locus heterogeneity - ocular albinism is x- linked recessive
Adds an inorganic phosphate onto substrate without using ATP

15. What lab value can distinguish orotic aciduria from ornithine transcarbamoylase def?
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
OTC has hyperammonemia - orotic aciduira does not

16. What does a western blot use for its sample
Catabolic processes to carry reducing equivalents away as NADH
Inhibits the Na/K pump by binding the K side
Protein
Tropoelastin with fibrillin scafolding

17. in a 100 meter sprint Where does energy come from
Stored ATP - creatine phosphate - anaerobic glycolysis
Binds 50S - blocking translocation
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

18. What is the RDE of ketogenesis
More than 1 codon may code for the same amino acid
HMG- CoA synthase
Oxalacetate
Core proteins

19. What does hormone sensitive lipase do
Coenzyme A - lipoamide
Mebendazole/thiabendazole
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
Degradation of TG stored in adipocytes

20. What does DNA poly I do?
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year
Acetly- CoA - CO2 - NADH

21. What metabolic rxns occur in the mitochondria
Schilling test
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Neural tube
GAA

22. What is pleiotropy and given an example
Leu - lys
Microtubules
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Carbomoyl phosphate synthetase II

23. What happens in the first stage of collagen synthesis - and Where does it happen
Glutamine PRPP amidotransferase
Cri du chat
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

24. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Tropoelastin with fibrillin scafolding
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Removal of N or C termal propeptides from zymogens to generate mature proteins

25. What substances are uncouling agents
Supply sufficient glucose to brain and RBCs and to preserve protein
Ile - phe - thr - trp
Arg and his inc in histones Which bind negatively charged DNA
2 -4 DNP - aspirin

26. How do glucagon/epi lead to glycogenolysis
Achondroplasia
Glucose -6 phosphate
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

27. What does lactase deficiency cause
Phenytoin - MTX - and sulfonamides
Citrate - acetyl coa from mito to cyto
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects

28. How many nucTIDEs is a tRNA and What does the secondary sturcture form
Anabolic processes as a supply of reducing equivalents
Transmitted only through mother - all offspring of affected females may show signs of disease
Poly A polymerase - signal is AAUAA
75 to 90 - cloverleaf

29. What tissue samples are used for karyotyping
Mutated dystrophin gene - less severe - adolescence
Blood - bone marrown - amniotic fluid - placental tissue
Accelearted muscle breakdown
IDL

30. What happens in vit B2 def
One
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Keep glutathione reduced so it can detoxify free radicals and peroxides
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

31. ADPKD is associated with What additional conditions
After day 1
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Dopamine beta hydroxylase

32. What is the mutation in beckers muscular dystrophy - What is the severity and time of onset
Wrinkles and acne
P+q = 1
Mutated dystrophin gene - less severe - adolescence
Anabolic processes as a supply of reducing equivalents

33. What does an umabiguous genetic code refer to...
Each codon specifies only 1 amino acid
Microarrays
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes

34. What are the glucogenic/ketogenic amino acids
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Ile - phe - thr - trp
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
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

35. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Fasting
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
FAP
Deamination

36. 90% of ADPKD cases are due to a mutation In what gene
NADH - NADPH - FADH2
DNA
APKD1 on chromosome 16
Mucus secreting globlet cells and antibody secreting plasma cells

37. What is the RDE of the urea cycle
Ca/calmodulin in muscle to coordinate with muscle activity
Flank pain - hematuria - HTN - progressive renal failure
Carbomoyl phosphate synthetase I
ATP

38. What are the symptoms of vit A def
Nonsense > missense > silent
Night blindness - dry skin
Acetyl - CoA to malonyl - CoA (2C to 3C)
Purines= A - G pyrimidine = C - T (U)

39. What does apoE do
Ile - phe - thr - trp
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Mediates extra remnant take up
Targets the proteins for lysosome

40. What is heteroplasmy
Fed
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
2 rings
PFK - rate limiting enzyme

41. What is the breakdown product of dopamine
HVA
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
N to C
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

42. How does ethanol induce hypoglycemia
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Exons
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

43. progressive neurodegeneration - developmental delay - cherry red spot on macula - lysosomes with onion skin - NO hepatosplenomegaly
Protein kinase A
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Mediates chylomicron secretion

44. What are the priorities for the body in fasting and starvation
Connective tissue
RRNA
Supply sufficient glucose to brain and RBCs and to preserve protein
Griseofulvin

45. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
AR
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Inc melt - dec fluidity

46. What two pathways is carbomoyl phosphate involved in - and what enzyme deficiency leads to a build of carbamoyl phosphate leading to what element in pyrimidine synthesis
Malapsorption syndromes like sprue or CF or mineral oil intake
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
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

47. What defects characterize DiGeorge syndrome
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
CG- 3 > AT-2 - More CG content - melting point goes up
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Thymic - parathyroid and cardiac

48. What are the results of CF on male fertility
Males are infertile due to bilateral absence of vas deferens
TRNA
Binds to LDL receptor - mediates VLDL secretion
Unmethylated - newly synthesized - HNPCC

49. How many ATP are created by aerobic metobolism of glucose in muslce via what shuttle
Von Gierke's - Pompe - Cori - McArdle
30 - glycerol -3- phosphate shuttle
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

50. What defects characterize velocardiofacial syndrome
Thymic - parathyroid and cardiac
Foliage - small reserve in liver - eat green leaves
Palate - facial and cardiac defects
CTG