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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 in carnitine def
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
1 kind with multiple subunits
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Terminal regions - tropocollagen

2. What is the hardy weinberg allele prevalence
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
P+q = 1
PMNs
Adds 2 carbon with the help of biotin

3. progressive neurodegeneration - hepatosplenomegaly - cherry red spot on macula - foam cells
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
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Neimann - pick - sphingomyelinase - sphingomyelin - AR
2 rings

4. What are possilbe presentation for galactokinase def
Disease
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Failure to track objects or develop a social smile
Colchicine

5. Which anti gout drugs work on microtubules
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Colchicine
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis

6. How do cardia glycosides work
GAA
ATP
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Free ribosomes

7. What else can phosphoylate phosphorylase kinase
Ca/calmodulin in muscle to coordinate with muscle activity
ATP - citrate
PFK - rate limiting enzyme
VMA

8. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Supply sufficient glucose to brain and RBCs and to preserve protein
Neurofibromatosis type 1 (von Recklinghausens disease)
Alpha - ketoglutarate dehydrogenase complex

9. What creates the musty body odor in PKU
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Glycine
Disorder of aromatic amino acid metabolism

10. What are the results of unbalanced translocation
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
O- oligosaccharaides
Alpha 1 -6 and alpha 1 -4
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

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

12. What do neurofilaments stain for
Neurons
Exons
Paclitaxel
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

13. What fxn does glucokinase serve in the liver
Uses ATP to add high energy phophate group onto substrate
Nonsense > missense > silent
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
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

14. Which anticancer drugs work on microtubules
Acetyl - CoA carboxylase (ACC)
Tropoelastin with fibrillin scafolding
Vincritsine/vinblastine
Proton gradient

15. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
GTP
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Huntingtons
30 - glycerol -3- phosphate shuttle

16. What is a missense mutation
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Changed AA (convservative - new AA is similar in chemical structure)
Inc insulin - dec cAMP - dec PKA

17. Describe the structure of cilia
Phenytoin - MTX - and sulfonamides
9+2 arrangement of microtubules
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Targets the proteins for lysosome

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

19. What is the order of severity for the different types of mutations
More than 1 codon may code for the same amino acid
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
Nonsense > missense > silent
Inhibits RNA polymerase II - found in death cap mushrooms

20. What happens on the nonoxidative arm of the HMP shunt and What is the key enzyme and cofactor
APKD1 on chromosome 16
Consesus sequenec of base pairs
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Mitochondria

21. What is the limiting reagent in EtOH metabolism
NAD+
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Avidin
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

22. What is the most abundant type of RNA
Keep glutathione reduced so it can detoxify free radicals and peroxides
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
RRNA
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

23. What happens in vit D excess
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Fasting
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

24. Which enzyme involved in RNA synthesis does not require a template
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Poly A polymerase - signal is AAUAA
Adds an inorganic phosphate onto substrate without using ATP
Microarrays

25. What is the Name and fxn of vit B12
Neg to pos
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Inc vit B6
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

26. What does the golgi assemble proteoglycans from
Base + ribose
Proline and glycine (non glycosylated forms)
Disorder of aromatic amino acid metabolism
Core proteins

27. How does abetalipoproteinemia present and What is the defect
Chylomicrons
No - its non homologous
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
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

28. Severe fasting hypoglycemia - inc glycogen storage in liver - inc blood lactate - hepatomegaly - dz and def enzyme
Arg - lys - his - arg is most basic - has has no charge at body pH
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Von gierkes - glucose 6 phosphatase
Anabolic processes as a supply of reducing equivalents

29. What is the RER called in neurons and What is made there
APC on chromosome 5
Phenylethamolamine N methyl transferase
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Nissl body - enzyme and NTs

30. What shape does the RNA generate during splicing and why?
AR
IMP precursor
Lariat shape in order and remove intron precisely and join 2 exons
HMG- CoA (HMG- CoA to mevalonate

31. Wgat substances directly inhibit mitochondrial ATPase - causing an inc in proton gradient - no ATP because pump is stopped
Biotin
Oligomycin
25OHD3
Neuralgia

32. How do labile celss grow and regenerate and What are examples
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Liver - ovaries - seminal vesicles
Huntingtons
Schwann cells - lens - retina - kidneys

33. decreases In what substances can cause PKU
Specific glycosylases - AP endonuclease
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
RNA
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

34. What is the TX for pyruvate dehydrogenase deficiency
Arg and his inc in histones Which bind negatively charged DNA
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Robertsonian translocation and mosaicism
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

35. What is the TX for CF and What does it do
Muscle
Malapsorption syndromes like sprue or CF or mineral oil intake
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Alkaptonuria - may have debiliating arthralgias

36. What causes Edwards syndrome and What is it
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
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
Catabolic processes to carry reducing equivalents away as NADH
RRNA

37. What is the amino acid precursor for histamine
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Defect in fibrillin
SAM
Histidine

38. Infection with what organism can cause B12 def
Adenosine to inosine
They yield only acetyl - CoA equivalents
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Diphyllobothrium latum

39. Which are the acidic amino acids
Asp and Glu
SnRNPs and other proteins
Mediates extra remnant take up
CarTWOlage

40. Why does alpha amanitin cause liver failure and Where is it found
Oligomycin
Neimann - pick - sphingomyelinase - sphingomyelin - AR
B-100 - CII and E
Inhibits RNA polymerase II - found in death cap mushrooms

41. What happens on the oxidative arm of the HMP shunt and What is the key enzyme
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Glutamate
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Orotic acid to UMP

42. Type IV BM
Base + ribose + phosphate (3' -5') phosphodiester bond
4 under the floor
Tryptophan
Same as sprint + OXPHOS

43. What are the results of CF on male fertility
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Males are infertile due to bilateral absence of vas deferens
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Alpha 1 -6 and alpha 1 -4

44. Describe the location and fxn of the Na/K ATPase
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
O- oligosaccharaides

45. peripheral neuropathy of hands/feet - angiokeratomas - CV/renal disease - dz - def enzyme - acc substrate - inherit
Phenylalanine
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
25OHD3
Marasmus - muscle wasting

46. What is I cell disease
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
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
75 to 90 - cloverleaf
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

47. What shuttle is used in fatty acid degredation and What does it move and From where to where
Carnitine shuttle - acyl - coa from cyto to mito
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Pseudomonas and s aureus
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)

48. What is a nonsense mutation
Change resulting in early stop codon
APKD1 on chromosome 16
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
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage

49. What does the golgi add to serine and threonine residues
Oral uridine administration
Nonsense > missense > silent
O- oligosaccharaides
Unwinds DNA template at replcation fork

50. What does the primary transcript combine with to form the spliceosome
Scrutinizes - hydrolyzes the bond
SnRNPs and other proteins
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Mediates extra remnant take up