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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 happens with dry beriberi
Polyneuritis - symmetrical muscle wasting
In ER - glucose 6- P to glucose
Fasting
Cytosol

2. What is the breakdown product of dopamine
HVA
Kwashiorkor - small child with swollen belly
Inc vit B6
B100

3. What is proteasomal degredation
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Coenzyme A - lipoamide
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Attachment of ubiquitin to defective proteins tag them for breakdown

4. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Disease
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
1 ring

5. Type IV collagen is an important structural componenet of the BM for which 3 organs
Phenytoin - MTX - and sulfonamides
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Kidney - ears - eyes

6. What test is used for B12 def
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
40 - 60 - 80
Wrinkles and acne
Schilling test

7. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Hereditary spherocytosis
Acetly- CoA - CO2 - NADH
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

8. What happens with wet beriberi
Modifies N- oligosaccharides
Cytosol - F 1 -6 BP to fructose 6 Phosphate
High output cardiac failure - dilated cardiomyopathy - edema
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

9. cell signaling defect of fibroblast growth factor (FGF) receptor 3 - results in dwarfism - short limbs - head/trunk nl size - associated with advanced paternal age
Cri du chat
IDL
Achondroplasia
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

10. How does warfarin work
Tropoelastin with fibrillin scafolding
Ile - phe - thr - trp
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Vit K antagonist

11. What rxn does propionyl - CoA carboxylase catalyze
Mitochondria
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Proton gradient
Adds 2 carbon with the help of biotin

12. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Free ribosomes
Binds to LDL receptor - mediates VLDL secretion
Proline and lysine - vit C

13. What does high cholesterol or long saturated fatty acid content do to the melting temperature and fluidity
Tropoelastin with fibrillin scafolding
Inc melt - dec fluidity
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
NAD+

14. What lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
PCR - denaturation - annealing - elongation
FMR1 gene - methylation - associated with chromosomal breakage
Protective against malaria
Regulatory proteins that control cell cycle events; phase specific; activate CDKs

15. Where are FADH2 electrons transferred to...
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Comlex II
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
In ER - glucose 6- P to glucose

16. What causes maple syrup urine disease and What does it lead to...
Creat a nick in the helix to relieave supercoils created during replication
Wrinkles and acne
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
Secretion of abnl thick mucus that plugs lungs - pancreas - liver

17. Where is fructose 1 -6 bisphosphatase found and What does it do
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Coenzyme A - lipoamide
Glycogen and FFA oxidation; glucose conserved for final sprinting
P2 +2pq+ = 1

18. Name as many x- linked recessive disorders as you can

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19. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Glycogen phosphorylase
HGPRT - defective purine salvage - excess uric acid production
32 - malate aspartate shuttle

20. What is the hardy weinberg allele prevalence
TTP
Blood - bone marrown - amniotic fluid - placental tissue
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
P+q = 1

21. What is the origin of replication
Debranching enzyme
Particular sequence of DNA where replicatino begins - may be single of multiple
Glycogenolysis to form glucose
HVA

22. What lab technique is use to profile gene expression levels of thousands of genes simultaneously to study certain diseases and treatments
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Poly A polymerase - signal is AAUAA
Microarrays
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

23. What is the longest time of RNA and shortest
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
MRNA - tRNA
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
APC on chromosome 5

24. How many rings do purines have
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
IDL
2 rings
Nature and severity of phenotype vary from 1 individual to another - NF type 1

25. In which state is PFK-2 active
Fed
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Superoxide dismutase
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

26. What does Alports syndrome cause and why
Fasting
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
Result from phagocytic removal of heinz bodies my macs - G6PD def
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive

27. What is the Name and function of vit B2
Asp and Glu
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
LCAT (lecithin cholesterol acyltransferase)
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

28. What CETP do
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
Cartilage - hyaline - vitreous body - nucleus pulposus
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Ketone - methyl

29. What is the fxn of vit D
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
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
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
SnRNPs and other proteins

30. What is the Name and fxn of vit B12
NAD+
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

31. What happens in vit D def
3' end (with CCA)
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
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
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)

32. What are purines made from
IMP precursor
Dec methionine - inc cystiene - inc B12/folate
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

33. How does abetalipoproteinemia present and What is the defect
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
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
Orotic acid to UMP

34. Gene imprinting implies that How many alleles are active at a single locus
One
Each codon specifies only 1 amino acid
Phenylalanine hydroxylase
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

35. What is the breakdown product of NE
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
VMA
NF2 on chromosome 22
Methionine encode by only 1 codon (AUG)

36. What is disulfiram used for
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Skin
Liver - also in kidney and gut epithelium
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons

37. What initiates protein synthesis
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Glycogen synthase
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
Inc melt - dec fluidity

38. What are the purely ketogenic amino acids
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Colchicine
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Leu - lys

39. What is mosaicism and give an example
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
Initiate chains
Marasmus - muscle wasting
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA

40. What does the TCA cycle produce per 1 acetyl CoA
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
MEN - 2A and 2B with ret gene
BOne
Glucose 6 phosphatase

41. How do stable (quiescent) cells grow and regenerate and What are examples
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
MRNA
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Avidin

42. What substances inhibit phosphofructokinase -1
P+q = 1
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
ATP - citrate
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

43. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
Citrate - acetyl coa from mito to cyto
Autosomal recessive diseases
Antioxidant - protects RBCs and membrances from free radical damage
Promotor - TATA box - and CAAT box - AT rich

44. What are the results of unbalanced translocation
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Neimann - pick - sphingomyelinase - sphingomyelin - AR
Alpha 1 -4 glucosidase
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

45. What is the active form of vit D
HGPRT - defective purine salvage - excess uric acid production
HMG- CoA reductase
1 -25 OH2 D3 = calcitriol
B12 and folate

46. What are the results of CF on male fertility
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
ATP - citrate
Fasting
Males are infertile due to bilateral absence of vas deferens

47. What causes B12 def
Kwashiorkor - small child with swollen belly
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Autosomal recessive diseases
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

48. What are CDKs
Scrutinizes - hydrolyzes the bond
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Cyclin dependent kinases;constitutive and inactive

49. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
Medial dorsal nucleus of thalamus - mamillary bodies
Protective against malaria
LDL
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

50. What does primase do
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
RNA poly II
Makes RNA primer on which DNA poly III can initiate replication
Exons