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Biochemistry

Instructions:

Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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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 does a northern blot use as its sample
Zero
Neurofibromatosis type 1 (von Recklinghausens disease)
Inc vit B6
RNA

2. What causes Marfan syndrome
Microarrays
Defect in fibrillin
FMR1 gene - methylation - associated with chromosomal breakage
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

3. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Essential fructosuria - fructokinase AR
Proton gradient
Kwashiorkor - small child with swollen belly
Exons

4. In which structures do you find microtubules
SNP
Flagella - cilia - mitotic spindles
Wernicke - korsakoff - dry and wet beriberi
UDP glucose pyrophosphorylase

5. What are the 4 assumption of the Hardy Weinberg law
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Changed AA (convservative - new AA is similar in chemical structure)

6. What is uniparental disomy
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Stored ATP - creatine phosphate - anaerobic glycolysis
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

7. What are CDKs
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Zero
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
Cyclin dependent kinases;constitutive and inactive

8. In eukaryotes - What does RNA poly II make
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
MRNA
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Muscle

9. Type I bone
Alkaptonuria - may have debiliating arthralgias
Pyruvate - NAD+ - CoA
Oral uridine administration
BOne

10. Type III collagen
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Four

11. What are the findings in Lesch - Nyhan
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Assistance of upper extremities to stand up
Familial hypercholesterolemia - hyperlipidemia type IIA
Phenylketones in urine

12. What is the amino acid precuror for creatine - urea and nitric oxide
IDL
Arginine
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Hyperlipidemia

13. What are the symptoms of vit A excess
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Ile - phe - thr - trp

14. How do stable (quiescent) cells grow and regenerate and What are examples
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
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
Inc insulin - dec cAMP - dec PKA
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes

15. What does glycosylation of pro alpha chian yield and What is the structure
RER
Procollagen - triple helix of 3 alpha collagen chains
Free ribosomes
NADH - NADPH - FADH2

16. What is NADPH's role inside RBCs
Keep glutathione reduced so it can detoxify free radicals and peroxides
Met - val - arg his
MRNA - tRNA
Pyruvate - NAD+ - CoA

17. nucleotide repeat for fragile x
CGG
Niacin - constituent of NAD and NADP - derived from tryptophan
Neg to pos
Citrate - acetyl coa from mito to cyto

18. What substances are uncouling agents
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
2 -4 DNP - aspirin
Only processed RNA
F16BP

19. What is the RDE of the HMP shunt
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Glucose 6 phosphate dehydrogenase (G6PD)
G6PD
Orotate precursor - with PRPP added later

20. What happens with dry beriberi
Polyneuritis - symmetrical muscle wasting
40 - 60 - 80
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
High output cardiac failure - dilated cardiomyopathy - edema

21. What do the single stranded binding proteins do
Prevent strands from reannealing
Zero
NADPH
Particular sequence of DNA where replicatino begins - may be single of multiple

22. What is the activated carrier for Co2
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
Biotin
Rotenone - CN- - antimycin A - CO
Cleft palate - cardiac abnl - pregs test

23. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
No - its non homologous
Actin and myosin
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

24. Which phase of the HMP shunt is reversible and Which is irreversible
Oxidative is irreversible
Alanine
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Read from a fixed starting point as a continuous sequence of bases

25. In prokaryotes - What does makes the different types of RNA
Ribose 5- P to PRPP
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
1 kind with multiple subunits
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase

26. What is the energy source in the fed state right after a meal
CGG
Glycolysis and aerobic respiration
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

27. What does acetyl - CoA become before becoming palmitate
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Attachment of ubiquitin to defective proteins tag them for breakdown
HGPRT - defective purine salvage - excess uric acid production

28. What enzyme converts phenylalanine to tyrosin
Disease
Mediates chylomicron secretion
Phenylalanine hydroxylase
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20

29. What is heteroplasmy
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
LDL
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease

30. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Intermediate filaments
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR

31. What is the limiting reagent in EtOH metabolism
NAD+
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
NADH - NADPH - FADH2

32. How do glucagon/epi lead to glycogenolysis
ATP
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Silencers

33. What is the wernicke - korsakoff clinical picture
5' to 3'
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Locus heterogeneity - ocular albinism is x- linked recessive
CAG - 4

34. congenital deficiency of homogentisic acid oxidase in the degradative pathway of tyrosine to fumarate leading to dark connective tissue - brown pigmented sclera - urine turns black on standing - dz and worst complication
Huntingtons
Protective against malaria
CGG
Alkaptonuria - may have debiliating arthralgias

35. what findings are associated with marfans
Vit K antagonist
Attachment of ubiquitin to defective proteins tag them for breakdown
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Cartilage - hyaline - vitreous body - nucleus pulposus

36. What do B- complex vitamin deficiencies often result in
Dermatitis - glossitis - and diarrhea
Mcardle's - skeletal muscle glycogen posphorylase
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

37. What apolipoprotiens are on VLDL
B-100 - CII and E
Oxidative and nonoxidative - no ATP produced or used
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
1 -25 OH2 D3 = calcitriol

38. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
HDL
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Oligomycin
Fibrofatty replacement of muscle - cardiac myopathy

39. What is the breakdown product of NE
VMA
Fibroblast
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
EtOH dehydrogenase and acetaldehyde dehydrogenase

40. How do permanent cells grow and regenerate and What are examples of permanent cells
Neurons
Ca/calmodulin in muscle to coordinate with muscle activity
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Antioxidant - protects RBCs and membrances from free radical damage

41. What is maternal PKU
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
AMP - fructose 2 -6 BP
Neurofibromatosis type 1 (von Recklinghausens disease)
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

42. Describe the pathophys of the aorta in a pt with marfans - and the eyes
Glucose -6 phosphate
1 ring
Isocitrate dehydrogenase
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses

43. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
Free ribosomes
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Marfans

44. What are the symptoms of vit A def
African Americans and Asians
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Night blindness - dry skin
VMA

45. 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
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
II - VII - IX - X (1972) protein C and S
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate

46. What two cells are particularly rich in RER
Mucus secreting globlet cells and antibody secreting plasma cells
Degradation of TG stored in adipocytes
CAG
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

47. How is ATP used by the cell
CGG
Adds an inorganic phosphate onto substrate without using ATP
ATP hyrdolysis couple to energetically unfavorable rxns
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

48. What feedback inhibits hexokinase
Glucose -6 phosphate
Orotic acid to UMP
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

49. How many ATP are produced by anearobic glycolysis per molecule of glucose
Type II
Two
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Von Gierke's - Pompe - Cori - McArdle

50. What is the RDE of ketogenesis
HMG- CoA synthase
5' to 3'
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Superoxide dismutase