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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 is the target of the 3' hydroxyl attack
Poly A polymerase - signal is AAUAA
The triphosphate bond
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Carnitine shuttle - acyl - coa from cyto to mito

2. trinucleotide repeat for huntingtons
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
DTMP
Comlex II
CAG

3. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Schilling test
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Autosomal recessive diseases
Transmitted through both parents - affected mother may have affected children - affected father will have affected children

4. What happens in termination of proteins synthesis
Catabolic processes to carry reducing equivalents away as NADH
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Stop codon is recognized by release factor - and completed protein is released from ribosome
Dermatitis - alopecia - enteritis

5. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
FMR1 gene - methylation - associated with chromosomal breakage
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
Cre - lox system
Pyruvate - NAD+ - CoA

6. What does Ehlers Danlos cause and why
Fasting
PFK - rate limiting enzyme
Breaks down acyl - coa to acetyl coa groups in mito
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

7. Which RNA poly opens DNA at promotor site
RNA poly II
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
No - its non homologous
Flagella - cilia - mitotic spindles

8. What is the exception to genetic redundancy
African Americans and Asians
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
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Methionine encode by only 1 codon (AUG)

9. What does hormone sensitive lipase do
Degradation of TG stored in adipocytes
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Cri du chat
Lactate

10. What is the results of vit B1 def
Met - val - arg his
Inc melt - dec fluidity
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

11. What metabolic rxns occur in the cytoplasm
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Semiconservative - continuous and discontinuous strands (okazaki fragments)
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

12. What defects characterize DiGeorge syndrome
Thymic - parathyroid and cardiac
ATP hyrdolysis couple to energetically unfavorable rxns
Mediates extra remnant take up
Inc CPK and muscle biopsy

13. What is maternal PKU
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Autosomal recessive diseases
Inhibits 50S peptidyltransferase

14. What is the RDE of fatty acid synthesis
EtOH dehydrogenase and acetaldehyde dehydrogenase
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
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
Acetyl - CoA carboxylase (ACC)

15. What residues are hydroxylated in step 2 of collagen synthesis - and What does this require
Vit K antagonist
Malapsorption syndromes like sprue or CF or mineral oil intake
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Proline and lysine - vit C

16. What does cytokeratin stain for
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Hyperlipidemia
Polyneuritis - symmetrical muscle wasting
Epithelial cells

17. What substances are uncouling agents
Achondroplasia
MRNA
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
2 -4 DNP - aspirin

18. What tissues have only aldose reductase
Schwann cells - lens - retina - kidneys
B100 and E
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
HMP shunt

19. What enzyme adds Cl - to the H202 to makes bleach
Myeloperoxidase
Particular sequence of DNA where replicatino begins - may be single of multiple
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
O- oligosaccharaides

20. What is the function of folic acid
9+2 arrangement of microtubules
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
P+q = 1
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

21. 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
Mutated dystrophin gene - less severe - adolescence
PMNs
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

22. What tissue samples are used for karyotyping
Blood - bone marrown - amniotic fluid - placental tissue
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Zero

23. Type IV BM
Collagen
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
After day 1
4 under the floor

24. Which direction does kinesin go
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Neg to pos
Tyrosine
Thymic - parathyroid and cardiac

25. What are the irreversible enzymes of gluconeogenesis
LDL
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase

26. For eukaryotes - Where does replication begin?
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Consesus sequenec of base pairs
Anabolic processes as a supply of reducing equivalents
17 - 17 letters in von Recklinghausen

27. What enzyme degrades a small amount of glycogen in lysosomes
Stored ATP - creatine phosphate - anaerobic glycolysis
Oligomycin
Cyclin dependent kinases;constitutive and inactive
Alpha 1 -4 glucosidase

28. characterize x linked recessive
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
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
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
APC on chromosome 5

29. What else can phosphoylate phosphorylase kinase
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Krabbes - galactocerebrosidase - galactocerebroside - AR
Debranching enzyme
Ca/calmodulin in muscle to coordinate with muscle activity

30. What is the fxn of vit D
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Binds to LDL receptor - mediates VLDL secretion
Glycogen synthase
Kidney - ears - eyes

31. What is the energy source after day 3 of starvation
Eu - methionine - pro - formyl - methionine
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
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
32 - malate aspartate shuttle

32. What are covalent alterations
Alpha - ketoglutarate dehydrogenase complex
CAG
Phosphorylation - glycosylation - hydroxylation
TRNA

33. What is the RDE of glycogenolysis
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Glycogen phosphorylase
Prevent strands from reannealing
VMA

34. What substance inside the cells replenishes NADPH
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
G6PD
Site of steroid synthesis and detoxification of drugs and poisons

35. nucleotide repeat for fredreich's ataxia
Arginine
Same as sprint + OXPHOS
More than 1 codon may code for the same amino acid
GAA

36. What are the symptoms of vit A def
Neurons
Comlex II
CGG
Night blindness - dry skin

37. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Oxidative and nonoxidative - no ATP produced or used
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Wrinkles and acne
B-100 - CII and E

38. When does aspartate enter the urea cycle
After citruline
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
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
Terminal regions - tropocollagen

39. What are the findings in PKU
ATP and alanine
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Oxidative is irreversible
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

40. What is the most common urea cycle disorder and What is the mode of inheritance?
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Liver - ovaries - seminal vesicles
Glycogen synthase

41. What substance inside the cell serves to oxidize glutatione
Glycogen synthase
Coenzyme A - lipoamide
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Peroxide

42. What is the RDE of de novo purine synthesis
Pyruvate - NAD+ - CoA
Glutamine PRPP amidotransferase
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
III - joint dislocation - anuerysms - organ rupture

43. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
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
Promotor - TATA box - and CAAT box - AT rich
Rb and p53
Prokaryotic only - degrades RNA primer and fills in the gap with DNA

44. Which end of the tRNA is the amino acid bound to...

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45. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
SNP
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Uses ATP to add high energy phophate group onto substrate

46. Which cells are rich in smooth ER
Superoxide dismutase
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Inc CPK and muscle biopsy
Liver hepatocytes and steroid producing cells of the adrenal cortex

47. In what cell is collagen synthesis initiated
After citruline
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Achondroplasia
Fibroblast

48. What is the hardy weinber heterozygote prevalence
B-100 - CII and E
Removes phosphate group from substrate
2pq
Mutated dystrophin gene - less severe - adolescence

49. FAP is due to deletion On what gene On what chromosome
Each codon specifies only 1 amino acid
APC on chromosome 5
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Hyperlipidemia

50. In which state is FBPase -2 active
APKD1 on chromosome 16
Fasting
Dermatitis - alopecia - enteritis
Alanine