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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 form of amino acids are found in proteins
Liver - ovaries - seminal vesicles
No - its non homologous
L form
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase

2. What does arsenic do and What are th results of poisoning
Avidin
Leu - lys
Four
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

3. What is the TX for PKU
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Phenylalanine
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
2 rings

4. What are the complications/signs of familial hypercholesterolemia
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
Tryptophan
Biotin
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20

5. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Inc insulin - dec cAMP - dec PKA
Marfans
RRNA

6. What is the function of folic acid
Disorder of aromatic amino acid metabolism
5' of the incoming nucleotide
PMNs
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA

7. What is the target of the 3' hydroxyl attack
Seals.
Four
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
The triphosphate bond

8. What does the deletion of the dystrophin gene lead to...
Essential fructosuria - fructokinase AR
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Orotate precursor - with PRPP added later
Accelearted muscle breakdown

9. Where does gluconeogenesis primarily happen and What are other sites where the enzymes are located
Liver - also in kidney and gut epithelium
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
Read from a fixed starting point as a continuous sequence of bases
Autosomal recessive diseases

10. What does the TCA cycle produce per 1 acetyl CoA
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Methionine encode by only 1 codon (AUG)
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Oxidative is irreversible

11. What are the fetal screening measures for Down
3' end (with CCA)
Paclitaxel
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US

12. What tissues have both enzymes of sorbitol metabolism
Glucose - 2Pi - 2ADP - 2NAD+
Liver - ovaries - seminal vesicles
Liver - also in kidney and gut epithelium
CGG

13. What is the breakdown product of epi
Reads usual codon but inserts wrong AA
CarTWOlage
RER
Metanephrine

14. What reaction does adenosine deaminase normally catalyze
Adenosine to inosine
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
African Americans and Asians

15. How does ethanol induce hypoglycemia
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
Antioxidant - protects RBCs and membrances from free radical damage
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

16. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Euchromatin
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
IDL
Removal of N or C termal propeptides from zymogens to generate mature proteins

17. In what cell is collagen synthesis initiated
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Fibroblast
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Transfers methyl units

18. What is the RDE of fatty acid synthesis
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Acetyl - CoA carboxylase (ACC)
Niacin - constituent of NAD and NADP - derived from tryptophan
Sucrose = glucose + fructose - lactose = glucose + galactose

19. What is the energy source in the fed state right after a meal
Terminal regions - tropocollagen
Glycolysis and aerobic respiration
1 kind with multiple subunits
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

20. What is the hardy weinberg allele prevalence
Lysine and arginine
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
P+q = 1
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia

21. What is the result of vit B5 def
CAG
No
Particular sequence of DNA where replicatino begins - may be single of multiple
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

22. What is the activated carrier for Acyl
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Coenzyme A - lipoamide
Glycogen phosphorylase

23. trinucleotide repeat for huntingtons
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Glycine - aspartate - glutamine
Seals.
CAG

24. What catacholamine step is SAM required for
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Post to neg
APRT + PRPP
Conversion of NE to epi

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

26. Describe the replication fork
Paclitaxel
Four
Y shaped region along the DNA template where leading nad lagging strands are synthesized
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

27. What does the ELISA test for
HMG- CoA (HMG- CoA to mevalonate
Phenylethamolamine N methyl transferase
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
B100

28. What are the glucogenic essential amino acids
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
Met - val - arg his
MEN - 2A and 2B with ret gene
Post to neg

29. what disease can cause pellagra
Liver and leafy veggies
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
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
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility

30. Where is EtOH dehydrogenase located
Leu - lys
Cytosol
Same AA - often base change in 3rd position of codon (tRNA wobble)
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

31. What is the RER called in neurons and What is made there
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Arg - lys - his - arg is most basic - has has no charge at body pH
Nissl body - enzyme and NTs
Marasmus - muscle wasting

32. Where is glucokinase found - What are the Km and Vmax - and what induces it
Mitochondria
4 under the floor
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

33. What does cytokeratin stain for
Alpha and beta tubulin - dimers have two GTP bound
Epithelial cells
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

34. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
Kwashiorkor - small child with swollen belly
32 - malate aspartate shuttle
MEN - 2A and 2B with ret gene
P2 +2pq+ = 1

35. What does beta oxidation do and Where does it occur
Catabolic processes to carry reducing equivalents away as NADH
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Breaks down acyl - coa to acetyl coa groups in mito
Semiconservative - continuous and discontinuous strands (okazaki fragments)

36. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Wernicke - korsakoff - dry and wet beriberi
Pyruvate - NAD+ - CoA
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Transfers methyl units

37. What collagen type is most frequently affected in ehlers danlos and What are common complications
Von gierkes - glucose 6 phosphatase
Neuralgia
Antibiotic use or excessive ingestion of raw eggs
III - joint dislocation - anuerysms - organ rupture

38. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Williams syndrome
Glucose -6 phosphate
Dec DNA - dec lymphos leads to SCID
Binds to LDL receptor - mediates VLDL secretion

39. What is the treatment for cystathionine synthase def
Inc dicarboxylic acids - dec in glucose and ketones
Avidin
Vincritsine/vinblastine
Dec methionine - inc cystiene - inc B12/folate

40. When are glycogen reserves depleted
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
After day 1
Keep glutathione reduced so it can detoxify free radicals and peroxides
F16BP

41. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
DTMP
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Post to neg

42. What is the activated carrier for methyl groups
Scrutinizes - hydrolyzes the bond
ATP and methionine
CG- 3 > AT-2 - More CG content - melting point goes up
SAM

43. What is axonemal dynein
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Ile - phe - thr - trp
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

44. Mild Hurlurs + aggressive behavior no corneal clouding
O- oligosaccharaides
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Night blindness - dry skin
TRNA

45. What enzymes metabolize fatty acids and amino acids
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Acetoacetate and beta hydroxybutyrate
1 kind with multiple subunits
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

46. In which state is FBPase -2 active
Fasting
CTG
Glycolysis and aerobic respiration
Anchor muscle fibers - primarily in skeletal and cardiac muscle

47. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Actin and myosin
Inc insulin - dec cAMP - dec PKA
Read from a fixed starting point as a continuous sequence of bases
Von hippel lindau - 3

48. How do glucagon/epi lead to glycogenolysis
Oligomycin
Transfers methyl units
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Collagen

49. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Hereditary spherocytosis
Neither of 2 alleles is dominant - blood groups
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Familial hypercholesterolemia - hyperlipidemia type IIA

50. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
Conversion of NE to epi
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Ribos first then deoxyribos with ribonucleotide reductase
Defect in fibrillin