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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. What are the water soluble vitamins - which ones are stored
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Marasmus - muscle wasting
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Four

2. cardiomegaly - systemic findings leading to early death - dz and enzyme

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3. cell signaling defect of fibroblast growth factor (FGF) receptor 3 - results in dwarfism - short limbs - head/trunk nl size - associated with advanced paternal age
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Glucose 6 phosphatase
Glycine - aspartate - glutamine
Achondroplasia

4. in a 100 meter sprint Where does energy come from
Microtubules
Orotate precursor - with PRPP added later
Stored ATP - creatine phosphate - anaerobic glycolysis
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

5. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Lactate
Deamination
By inhibiting formation of the initiation complex and cause misreading of mRNA
Fibrofatty replacement of muscle - cardiac myopathy

6. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Tryosine hydroxylase
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast

7. What apolipoprotiens are on VLDL
Glutamine PRPP amidotransferase
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Supply sufficient glucose to brain and RBCs and to preserve protein
B-100 - CII and E

8. Milder form of type I with nl blood lactate levels - dz and enzyme

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9. How does cytosine become uracil
Neurons
Deamination
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
NF2 on chromosome 22

10. What does a dehydrogenase do
5' of the incoming nucleotide
Alpha - ketoglutarate dehydrogenase complex
Oxidizes substrate
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

11. What is the purpose of the HMP shunt
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Eu - methionine - pro - formyl - methionine
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma

12. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Type II
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
Intermediate filaments
Acetyl - CoA

13. What does DNA poly I do?
Neurofibromatosis type 1 (von Recklinghausens disease)
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15

14. What are the results of pancreatic insuff in CF
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Malabsorption and steatorrhea (ADEK)
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
HMP shunt

15. How many nucTIDEs is a tRNA and What does the secondary sturcture form
Phenylalanine hydroxylase
75 to 90 - cloverleaf
Marfans
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

16. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
X- linked recessive
LDL
UGA - UAA and UAG
5' of the incoming nucleotide

17. Giving folate during early pregnancy is important to prevent what birth defects
1 kind with multiple subunits
Nissl body - enzyme and NTs
Neural tube
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

18. What test is used for B12 def
Schilling test
Palate - facial and cardiac defects
Same AA - often base change in 3rd position of codon (tRNA wobble)
Rotenone - CN- - antimycin A - CO

19. What are the findings in PKU
Antioxidant - protects RBCs and membrances from free radical damage
Locus heterogeneity - ocular albinism is x- linked recessive
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

20. What is the RDE of glycogen synthesis
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
In ER - glucose 6- P to glucose
Glycogen synthase

21. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Oxidative and nonoxidative - no ATP produced or used

22. What is axonemal dynein
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Disease
Conversion of NE to epi
Unwinds DNA template at replcation fork

23. What does the vimentin stain for
Connective tissue
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Proton gradient
Mucus secreting globlet cells and antibody secreting plasma cells

24. What do DNA topoisomerases do
B-100 - CII and E
Biotin
Creat a nick in the helix to relieave supercoils created during replication
CGG

25. What else can phosphoylate phosphorylase kinase
3' end (with CCA)
Ca/calmodulin in muscle to coordinate with muscle activity
RNA poly II
Phenytoin - MTX - and sulfonamides

26. 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
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Williams syndrome
Change resulting in early stop codon
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

27. What substance inside the cell serves to oxidize glutatione
Accelearted muscle breakdown
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Disease
Peroxide

28. What is the activated carrier for Acyl
Changed AA (convservative - new AA is similar in chemical structure)
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
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Coenzyme A - lipoamide

29. How do tetracyclines work
Protein
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
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Leu - lys

30. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Prevent strands from reannealing
Myeloperoxidase
Seals.
Marasmus - muscle wasting

31. What is the result of vit B5 def
Acetly- CoA - CO2 - NADH
ATP
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
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

32. What does universal genetic code refer to and What are some exception
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Type II
30 - 50 - 70
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

33. inc glycogen in muscle but can't break it down - painful muscle cramps - myglobinuria with strenuous exercise - dz and enzyme

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34. What is the RDE of de novo pyrimidine synthesis
Carbomoyl phosphate synthetase II
Lysine and leucine
Hereditary spherocytosis
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

35. What is dominant negative mutation and give an example
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
ADPKD
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Unwinds DNA template at replcation fork

36. Where is EtOH dehydrogenase located
Cytosol
Lysine and arginine
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
32 - malate aspartate shuttle

37. What is the smallest mutation a mircoarray can detect
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
By inhibiting formation of the initiation complex and cause misreading of mRNA
SNP
Base + ribose + phosphate (3' -5') phosphodiester bond

38. what happens in acyl coa dehyrdogenase def
Dermatitis - enteritis - alopecia - adrenal insuff
Inc dicarboxylic acids - dec in glucose and ketones
Same AA - often base change in 3rd position of codon (tRNA wobble)
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

39. What causes biotin def
Antibiotic use or excessive ingestion of raw eggs
Promotor - TATA box - and CAAT box - AT rich
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
Glutamine PRPP amidotransferase

40. What does osteogenesis imperfecta causes and why
Rotenone - CN- - antimycin A - CO
75 to 90 - cloverleaf
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
Mucus secreting globlet cells and antibody secreting plasma cells

41. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Terminal regions - tropocollagen
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora

42. What two enzymes are involved in EtOH metabolism
Neither of 2 alleles is dominant - blood groups
EtOH dehydrogenase and acetaldehyde dehydrogenase
Malapsorption syndromes like sprue or CF or mineral oil intake
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15

43. What are uncoupling agents
Alpha and beta tubulin - dimers have two GTP bound
Active secretion in lungs and GI - reabsorbs in skin
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
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

44. What ribosomes do prokaryotes have
LDL
Assistance of upper extremities to stand up
30 - 50 - 70
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

45. What is a nonsense mutation
Change resulting in early stop codon
Wrinkles and acne
Carnitine shuttle - acyl - coa from cyto to mito
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

46. Which type of chromatin is less condensed - transcriptionally active - sterically accesible
Elastase - inhibited by alpha1 antitrypsin
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Euchromatin
L form

47. Which amino acids are elastin rich in
Nonsense > missense > silent
Proline and glycine (non glycosylated forms)
Vincritsine/vinblastine
Polycystic liver disease - berry aneurysm - mitral valve prolapse

48. Where is PEP carboxykinase found - What does it do - and What does it require
African Americans and Asians
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Alkaptonuria - may have debiliating arthralgias
Metanephrine

49. What does the TCA cycle produce per 1 acetyl CoA
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Purines= A - G pyrimidine = C - T (U)
Scrutinizes - hydrolyzes the bond
Two

50. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
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
CTG
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle