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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. When are glycogen reserves depleted
Nonsense > missense > silent
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
CGG
After day 1

2. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Huntingtons
Tuberous sclerosis
2pq
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses

3. How does OTC def present
32 - malate aspartate shuttle
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
Pyruvate - NAD+ - CoA
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

4. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
LCAT (lecithin cholesterol acyltransferase)
Skin
LDL
G6PD

5. What is the energy source after day 3 of starvation
Adipse tissue stores - keton bodies become the main source of energy fo the brain and heart - after these are depleted - vital protein degradation accelerates - leading to organ failure and death
Dermatitis - glossitis - and diarrhea
Ribose 5- P to PRPP
ADPKD

6. What fxn does glucokinase serve in the liver
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Lacks glucose 6 phophatase
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

7. 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
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Oligomycin
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

8. Which phase of the HMP shunt is reversible and Which is irreversible
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
UGA - UAA and UAG
Oxidative is irreversible
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1

9. What metabolic rxns occur in the cytoplasm
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Mediates chylomicron secretion
Breaks down acyl - coa to acetyl coa groups in mito
MRNA

10. What sugar is sorbitol converted to and via what enzyme - and What can happen in cells lacking this enzyme
ATP hyrdolysis couple to energetically unfavorable rxns
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Nine

11. In a 1000 meter run - Where does energy come from
Oxidative and nonoxidative - no ATP produced or used
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Same as sprint + OXPHOS
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

12. Where is acetaldehyde located
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Mutated dystrophin gene - less severe - adolescence
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Mitochondria

13. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
17 - 17 letters in von Recklinghausen
5' of the incoming nucleotide

14. What is the function of Zinc
AR
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
MEN - 2A and 2B with ret gene
In ER - glucose 6- P to glucose

15. How is ammonium transported from muscle to the liver for urea cycle
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
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Alkaptonuria - may have debiliating arthralgias
Cartilage - hyaline - vitreous body - nucleus pulposus

16. What polar group does guanine have - and what non polar group does thymine have
Asp and Glu
40 - 60 - 80
5' of the incoming nucleotide
Ketone - methyl

17. Type I collagen
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Site of steroid synthesis and detoxification of drugs and poisons

18. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
Comlex II
CAG
Ribos first then deoxyribos with ribonucleotide reductase
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA

19. What is the result of vit B5 def
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
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Dermatitis - enteritis - alopecia - adrenal insuff
Achondroplasia

20. How do cardia glycosides work
Degradation of TG stored in adipocytes
Mutated dystrophin gene - less severe - adolescence
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Fed

21. What is the function of folic acid
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
SNP

22. What bone disorder has x linked dominant inheritance
Actin and myosin
Ca/calmodulin in muscle to coordinate with muscle activity
In ER - glucose 6- P to glucose
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

23. What is the amino acid precuror for creatine - urea and nitric oxide
Arginine
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Krabbes - galactocerebrosidase - galactocerebroside - AR
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

24. What tissues have only aldose reductase
Alpha1 antitrypsin
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
Schwann cells - lens - retina - kidneys
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

25. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Avidin
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
P2 +2pq+ = 1
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive

26. What is incomplete penetrence and give an example
Not all individuals with a mutant genotype show the mutant phenotype
Von hippel lindau - 3
X- linked recessive
Cleft palate - cardiac abnl - pregs test

27. What is uniparental disomy
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Assistance of upper extremities to stand up
Wernicke - korsakoff - dry and wet beriberi

28. What defects characterize velocardiofacial syndrome
After day 1
II - VII - IX - X (1972) protein C and S
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Palate - facial and cardiac defects

29. decreases In what substances can cause PKU
HVA
Tyrosine
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Targets the proteins for lysosome

30. Why is albinism inheritnace varialbe due to...
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Locus heterogeneity - ocular albinism is x- linked recessive
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

31. How do microtubules grow and collapse
Consesus sequenec of base pairs
Uses ATP to add high energy phophate group onto substrate
Grows slowly - collapses quickly
B12 and folate

32. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Inhibits 50S peptidyltransferase
Silencers
Actin and myosin
Poly A polymerase - signal is AAUAA

33. What is the result of vit B5 def
FISH
Medial dorsal nucleus of thalamus - mamillary bodies
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

34. What can vit B3 be used to treat
Hyperlipidemia
Dec DNA - dec lymphos leads to SCID
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

35. What is the activated carrier for aldehyddes
TTP
Thymic - parathyroid and cardiac
Glutamine PRPP amidotransferase
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

36. How is Lesch Neyhan inherited
Schwann cells - lens - retina - kidneys
X- linked recessive
AMP - fructose 2 -6 BP
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

37. What is NAD+ generally used for
Wernicke - korsakoff - dry and wet beriberi
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Stored ATP - creatine phosphate - anaerobic glycolysis
Catabolic processes to carry reducing equivalents away as NADH

38. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
RNA poly II
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Essential fructosuria - fructokinase AR
FAP

39. What are the results of pancreatic insuff in CF
Connective tissue
Terminal regions - tropocollagen
After day 1
Malabsorption and steatorrhea (ADEK)

40. What is the RDE of de novo pyrimidine synthesis
Wrinkles and acne
32 - malate aspartate shuttle
B100
Carbomoyl phosphate synthetase II

41. What apolipoprotiens are on VLDL
Alpha 1 -4 glucosidase
Basement membrane or basal lamina
B-100 - CII and E
GTP

42. In eukaryotes - What does RNA poly III make
TRNA
PCR - denaturation - annealing - elongation
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Glutamate

43. What happens in vit D excess
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
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
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Lariat shape in order and remove intron precisely and join 2 exons

44. What does a defective Cl channel do
Marfans
LCAT (lecithin cholesterol acyltransferase)
Dopamine beta hydroxylase
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

45. What metabolic rxns occur in the mitochondria
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Uses ATP to add high energy phophate group onto substrate
Marfans
Adds 2 carbon with the help of biotin

46. In prokaryotes - What does makes the different types of RNA
CAG
2 rings
1 kind with multiple subunits
Dopamine beta hydroxylase

47. What causes Edwards syndrome and What is it
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
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
Changed AA (convservative - new AA is similar in chemical structure)
THFs

48. Which antihelminthe drugs work on microtubules
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Niacin - constituent of NAD and NADP - derived from tryptophan
Elastase - inhibited by alpha1 antitrypsin
Mebendazole/thiabendazole

49. What are the characteristics of angelmans syndrome and How does it occur
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
No
Orotate precursor - with PRPP added later
Liver and leafy veggies

50. What neuroanatomical strutures are injured in wernicke - korsakoff
No - its non homologous
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Medial dorsal nucleus of thalamus - mamillary bodies
Locus heterogeneity - ocular albinism is x- linked recessive