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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 tissues have only aldose reductase
Dopamine beta hydroxylase
Disorder of aromatic amino acid metabolism
Schwann cells - lens - retina - kidneys
Terminal regions - tropocollagen

2. What regulates whether FBPase -2 or PFK-2 is active
Degredation of dietary TG in small intestine
Orotic acid to UMP
Protein kinase A
Tyrosine

3. Which are the basic amino acids
Glutamate
Arg - lys - his - arg is most basic - has has no charge at body pH
Stop codon is recognized by release factor - and completed protein is released from ribosome
Skin

4. What causes patau's syndrome and What is it
Alpha 1 -4 glucosidase
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

5. What form of amino acids are found in proteins
L form
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
CGG
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

6. Where is vit A found in the diet
Dec DNA - dec lymphos leads to SCID
Liver and leafy veggies
Ca/calmodulin in muscle to coordinate with muscle activity
ATP hyrdolysis couple to energetically unfavorable rxns

7. What are the functinos of vitamin A
Alpha and beta tubulin - dimers have two GTP bound
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
HGPRT - defective purine salvage - excess uric acid production
Inhibits 50S peptidyltransferase

8. What does Alports syndrome cause and why
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Bruton's agammaglobulinemia - wiskott - aldrich - fabrys disease - G6PD def - ocular albinism - Lesch - Nyhan syndrome - Duchenne and Becker Muscular Dystrophy - hunter's syndrome - hemophilia A and B
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year

9. What is the TX for PKU
Type II
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Oxidizes substrate
Antibiotic use or excessive ingestion of raw eggs

10. What are covalent alterations
Enhancers
Von gierkes - glucose 6 phosphatase
Phosphorylation - glycosylation - hydroxylation
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms

11. Is there any requirement for homology in NHEJ
No - its non homologous
Oligomycin
Phosphofructokinase 1
Two

12. What initiates protein synthesis
Ca/calmodulin in muscle to coordinate with muscle activity
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue

13. What is the amino acid precursor for catecholamines
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Phenylalanine

14. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Hyperlipidemia
Dec DNA - dec lymphos leads to SCID
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

15. What 3 steps in RNA processing occur after transcription

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16. What happens in termination of proteins synthesis
SAM
Cartilage - hyaline - vitreous body - nucleus pulposus
5' to 3'
Stop codon is recognized by release factor - and completed protein is released from ribosome

17. What is pleiotropy and given an example
Foliage - small reserve in liver - eat green leaves
Proline and lysine - vit C
Hereditary spherocytosis
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes

18. Why enzyme breaks down elastin and what enzyme inhibits it
ATP hyrdolysis couple to energetically unfavorable rxns
Elastase - inhibited by alpha1 antitrypsin
LCAT (lecithin cholesterol acyltransferase)
Inc insulin - dec cAMP - dec PKA

19. Type IV collagen is an important structural componenet of the BM for which 3 organs
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Carnitine acyltransferase I
Kidney - ears - eyes

20. How do odd chain fatty acids participate in gluconeogenesis
32 - malate aspartate shuttle
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
X linked frame shif mutation
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

21. What neuroanatomical strutures are injured in wernicke - korsakoff
Medial dorsal nucleus of thalamus - mamillary bodies
GAA
Inhibits the Na/K pump by binding the K side
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O

22. In which direction is protein synthesized
Degredation of dietary TG in small intestine
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Makes RNA primer on which DNA poly III can initiate replication
N to C

23. What is mosaicism and give an example
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Vit K antagonist
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
Not all individuals with a mutant genotype show the mutant phenotype

24. What is variable expression and What is an example
Neg to pos
Glutamate
Nature and severity of phenotype vary from 1 individual to another - NF type 1
The triphosphate bond

25. Type IV collagen
Glucose -6 phosphate
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Purines= A - G pyrimidine = C - T (U)
Basement membrane or basal lamina

26. What enzyme adds Cl - to the H202 to makes bleach
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Myeloperoxidase
Lacks glucose 6 phophatase

27. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
Krabbes - galactocerebrosidase - galactocerebroside - AR
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20

28. What is the activated carrier for phosphoryl
ATP
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
Malonyl coa
2 -4 DNP - aspirin

29. What is the trinucleotide repeat in fragile X
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Lariat shape in order and remove intron precisely and join 2 exons
CGG
Fabrys - alpha galactosidase A - ceramide trihexoside - XR

30. What makes up a nucleotide

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31. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
P+q = 1
HGPRT - defective purine salvage - excess uric acid production
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Grows slowly - collapses quickly

32. How does OTC def present
Peroxide
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
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
Citrate - acetyl coa from mito to cyto

33. What is axonemal dynein
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Inc Cl - in sweat
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Mitochondria

34. What is the function and name of vit B6
Eu - methionine - pro - formyl - methionine
Phenytoin - MTX - and sulfonamides
HVA
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

35. What are cyclins
Acetyl - CoA
NADPH
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
F16BP

36. What are the results of unbalanced translocation
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Failure to track objects or develop a social smile
Neurofibromatosis type 1 (von Recklinghausens disease)
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

37. What apolipoproteins are on IDL
Mutated dystrophin gene - less severe - adolescence
B100 and E
More than 1 codon may code for the same amino acid
III - joint dislocation - anuerysms - organ rupture

38. What does a western blot use for its sample
Williams syndrome
Protein
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

39. Which RNA poly opens DNA at promotor site
Phosphorylation - glycosylation - hydroxylation
RNA poly II
Lysine and arginine
Night blindness - dry skin

40. What is the energy source in the fed state right after a meal
Nine
Glycolysis and aerobic respiration
Familial hypercholesterolemia - hyperlipidemia type IIA
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms

41. What does commaless - nonoverlapping genetic code refer to...
By inhibiting formation of the initiation complex and cause misreading of mRNA
Alpha 1 -6 and alpha 1 -4
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Read from a fixed starting point as a continuous sequence of bases

42. What substance inside the cell reduces glutatione
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
NADPH
Cartilage - hyaline - vitreous body - nucleus pulposus
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

43. What substance accumulates in galactokinase def and What is the clinical picture
Epithelial cells
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast

44. What is the hardy weinberg allele prevalence
SnRNPs
P+q = 1
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

45. 90% of ADPKD cases are due to a mutation In what gene
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
APKD1 on chromosome 16
Conversion of NE to epi
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility

46. What is the prevalence of an X- linked recessive disease in males and in females
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Q -
Neural tube
Eu - methionine - pro - formyl - methionine

47. What does cytokeratin stain for
Isocitrate dehydrogenase
Epithelial cells
Asp and Glu
Dermatitis - alopecia - enteritis

48. Type II cartilage
Mediates chylomicron secretion
CarTWOlage
Pyruvate to oxaloacetate (3C to 4C)
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

49. What is the breakdown product of dopamine
Debranching enzyme
Inhibit DNA gyrase specific for prokaryotic topoisomerase
HVA
Malonyl coa

50. Describe the location and fxn of the Na/K ATPase
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Poly A polymerase - signal is AAUAA
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
By inhibiting formation of the initiation complex and cause misreading of mRNA