Test your basic knowledge |

Biochemistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

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 is the breakdown product of epi
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Metanephrine
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Free ribosomes

2. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
CAG
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
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
Marasmus - muscle wasting

3. What does Ehlers Danlos cause and why
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
MEN - 2A and 2B with ret gene
Site of steroid synthesis and detoxification of drugs and poisons
Cyclin dependent kinases;constitutive and inactive

4. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Glycogenolysis to form glucose
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Lysine and arginine

5. What is the main source of folate
Stop codon is recognized by release factor - and completed protein is released from ribosome
Foliage - small reserve in liver - eat green leaves
Sucrose = glucose + fructose - lactose = glucose + galactose
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

6. What does acetyl - CoA become before becoming palmitate
UGA - UAA and UAG
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin

7. What apolipoproteins are on chylomicrons
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
HMP shunt
Hypoglycemia
B48 - AIV - CII - E

8. 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
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Williams syndrome
Carbomoyl phosphate synthetase II
Purines= A - G pyrimidine = C - T (U)

9. What happens on the oxidative arm of the HMP shunt and What is the key enzyme
NAD+
Autosomal recessive diseases
Enhancers
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

10. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
25OHD3
Type II
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Lysine and leucine

11. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Degredation of dietary TG in small intestine
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
CAG

12. What are bite cells and when do you see them
HMP shunt
Result from phagocytic removal of heinz bodies my macs - G6PD def
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
O- oligosaccharaides

13. What liberates glucose from glucose 6 P
Changed AA (convservative - new AA is similar in chemical structure)
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Glucose 6 phosphatase
X linked frame shif mutation

14. What does hepatic TG lipase do
Hypoglycemia
Degradation of TG remaining in IDL
Glucose - 2Pi - 2ADP - 2NAD+
IMP precursor

15. What substances inhibit phosphofructokinase -1
B100
Glucose - 2Pi - 2ADP - 2NAD+
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
ATP - citrate

16. What is proteasomal degredation
Attachment of ubiquitin to defective proteins tag them for breakdown
Read from a fixed starting point as a continuous sequence of bases
Von gierkes - glucose 6 phosphatase
Nonsense > missense > silent

17. What is linkage disequilibrium
Phenytoin - MTX - and sulfonamides
Kidney - ears - eyes
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA

18. Where do you find elastin and What does it do
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Ribos first then deoxyribos with ribonucleotide reductase
2 -4 DNP - aspirin
Inc insulin - dec cAMP - dec PKA

19. What does apoA 1 do
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Glycogenolysis to form glucose
Activates LCAT

20. What are the findings in Lesch - Nyhan
Blood - bone marrown - amniotic fluid - placental tissue
Muscle
Alpha - ketoglutarate dehydrogenase complex
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

21. What are the two transgenic strategies in mice
In ER - glucose 6- P to glucose
Phenylethamolamine N methyl transferase
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Leu - lys

22. What are the names and sources of the two types of vit D found in nature
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive

23. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Glucose 6 phosphatase
Elastase - inhibited by alpha1 antitrypsin
Marfans
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

24. What other inflammatory process can induce a hemolytic anemia in NADPH defieicnt patients
Adenosine to inosine
Tuberous sclerosis
Alpha - ketoglutarate dehydrogenase complex
Infection - free radicals generated by inflammatory response

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

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

26. What apolipoprotein is on LDL
HMG- CoA synthase
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
B100
2 -4 DNP - aspirin

27. what disease can cause pellagra
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
HMG- CoA (HMG- CoA to mevalonate
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
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

28. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Proline and lysine - vit C
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

29. In the chromatin structure - which histones form the octamer - and which ties the nucleosome beads together in a string?
Unmethylated - newly synthesized - HNPCC
More than 1 codon may code for the same amino acid
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

30. Which aspect of the spliceosome do patients with lupus make antibodies against
Epithelial cells
Specific glycosylases - AP endonuclease
SnRNPs
Diphyllobothrium latum

31. What is the activated carrier for phosphoryl
RRNA
B12 and folate
B-100 - CII and E
ATP

32. What do the single stranded binding proteins do
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Prevent strands from reannealing
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate

33. What happens in a B12 def
Alpha1 antitrypsin
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Paclitaxel

34. Fluorescent DNA or RNA probe binds to specific gene of interest - used for specific localization of genes and direct visualization of anomalies - like microdeletions - at molecular level
Glycogen phosphorylase
FISH
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Protein

35. 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
Sulfation
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
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
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

36. Who typically has lactase def
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
African Americans and Asians
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

37. What is the name is fxn of vit B3
Malabsorption and steatorrhea (ADEK)
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Debranching enzyme
Niacin - constituent of NAD and NADP - derived from tryptophan

38. What does an umabiguous genetic code refer to...
Each codon specifies only 1 amino acid
CAG
Dopamine beta hydroxylase
CAG - 4

39. What are the symptoms of vit A excess
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
EtOH dehydrogenase and acetaldehyde dehydrogenase
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Inc melt - dec fluidity

40. What does glycosylation of pro alpha chian yield and What is the structure
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE
Procollagen - triple helix of 3 alpha collagen chains
Cleft palate - cardiac abnl - pregs test
Inhibits RNA polymerase II - found in death cap mushrooms

41. What are the results of CF on male fertility
Males are infertile due to bilateral absence of vas deferens
30 - 50 - 70
Protein
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US

42. What is RNAi used for
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
DsRNA promotes degradation of target mRNA knocking down gene expression
Changed AA (convservative - new AA is similar in chemical structure)
Huntingtons

43. What reaction does adenosine deaminase normally catalyze
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Adenosine to inosine
Mitochondria
1 ring

44. How does warfarin work
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Vit K antagonist

45. In eukaryotes - What does RNA poly III make
G6PD
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
Must be both activated and inactivated for cell cycle to progress
TRNA

46. What is sorbitol - how and why is it made
Paclitaxel
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Alcohol version of glucose - can trap glucose in cell - aldose reductase

47. What is the TX for pyruvate dehydrogenase deficiency
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Intermediate filaments
Dermatitis - alopecia - enteritis

48. What two proteins make up microtubules and how are they arranged
Read from a fixed starting point as a continuous sequence of bases
Seals.
Alpha and beta tubulin - dimers have two GTP bound
Orotic acid to UMP

49. How do labile celss grow and regenerate and What are examples
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
Each codon specifies only 1 amino acid
Myeloperoxidase
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles

50. What 3 syndromes are associated with vit B1 def
Protein
Wernicke - korsakoff - dry and wet beriberi
Pyruvate - NAD+ - CoA
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora