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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 does SAM do
3' end (with CCA)
Transfers methyl units
Oligomycin
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

2. What is locus heterogeneity and give an example
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Four
Nissl body - enzyme and NTs

3. What are the findings with homocystinuria and What amino acid is needs to be supplemented
Euchromatin
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Essential fructosuria - fructokinase AR

4. What is the TX for PKU
Prevent strands from reannealing
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Oxidative and nonoxidative - no ATP produced or used
Assistance of upper extremities to stand up

5. 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
TRNA
Defect in fibrillin
Glycogen synthase
FISH

6. What does NADPH oxidase deficiency result in and why
Defect in fibrillin
Microarrays
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

7. What do neurofilaments stain for
Promotor - TATA box - and CAAT box - AT rich
Neurons
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
Inhibit DNA gyrase specific for prokaryotic topoisomerase

8. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Zero
Active secretion in lungs and GI - reabsorbs in skin
Chylomicrons
HDL

9. What are the products for glycolysis
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Schwann cells - lens - retina - kidneys
Locus heterogeneity - ocular albinism is x- linked recessive
Silencers

10. What are the functinos of vitamin A
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
Polycystic liver disease - berry aneurysm - mitral valve prolapse
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

11. In eukaryotes - What does RNA poly II make
Fasting
MRNA
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Degredation of dietary TG in small intestine

12. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Stored ATP - creatine phosphate - anaerobic glycolysis
Sucrose = glucose + fructose - lactose = glucose + galactose
Isocitrate dehydrogenase
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

13. peripheral neuropathy of hands/feet - angiokeratomas - CV/renal disease - dz - def enzyme - acc substrate - inherit
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Paclitaxel

14. RNA poly can't proofread - but What can it do
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Initiate chains
Karyotyping
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

15. pyruvate carboxylase catalyzes what rxn
4 under the floor
Pyruvate to oxaloacetate (3C to 4C)
CG- 3 > AT-2 - More CG content - melting point goes up
Inc glucagon - inc cAMP - inc PKA

16. Where is fructose 1 -6 bisphosphatase found and What does it do
Cytosol - F 1 -6 BP to fructose 6 Phosphate
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
1 ring
Glutamate

17. In which structures do you find microtubules
Pyruvate - NAD+ - CoA
APRT + PRPP
Flagella - cilia - mitotic spindles
Neg to pos

18. NADPH are used In what 4 things
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Purines= A - G pyrimidine = C - T (U)
Same AA - often base change in 3rd position of codon (tRNA wobble)
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

19. What are covalent alterations
Phosphorylation - glycosylation - hydroxylation
Ketone - methyl
Comlex II
Oxidative is irreversible

20. What is a missense mutation
Changed AA (convservative - new AA is similar in chemical structure)
Basement membrane or basal lamina
B-100 - CII and E
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

21. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Eu - methionine - pro - formyl - methionine
Schwann cells - lens - retina - kidneys
Cytosol
Oxalacetate

22. Why can't muscle produce in gluconeogenesis
Not all individuals with a mutant genotype show the mutant phenotype
Lacks glucose 6 phophatase
Post to neg
30 - glycerol -3- phosphate shuttle

23. How is ammonium transported from muscle to the liver for urea cycle
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Tryptophan
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

24. What causes patau's syndrome and What is it
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+2 arrangement of microtubules
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE
Catabolic processes to carry reducing equivalents away as NADH

25. What is the Hardy Weinberg disease prevalence equation
Tyrosine
P2 +2pq+ = 1
30 - glycerol -3- phosphate shuttle
Creat a nick in the helix to relieave supercoils created during replication

26. What inhibits the carnitine shuttle
African Americans and Asians
Facial flushing
Malonyl coa
Citrate - acetyl coa from mito to cyto

27. What are bite cells and when do you see them
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
Breaks down acyl - coa to acetyl coa groups in mito
Result from phagocytic removal of heinz bodies my macs - G6PD def
One

28. What is the amino acid precursor for porphyrin and heme
Glycogen synthase
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Glycine
Schwann cells - lens - retina - kidneys

29. Where is glucokinase found - What are the Km and Vmax - and what induces it
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Disease
Males are infertile due to bilateral absence of vas deferens

30. What is the prevalence of an X- linked recessive disease in males and in females
Particular sequence of DNA where replicatino begins - may be single of multiple
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Q -
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15

31. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
Neuralgia
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
CG- 3 > AT-2 - More CG content - melting point goes up

32. What are the symptoms of vit A excess
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Arg and his inc in histones Which bind negatively charged DNA
Specific glycosylases - AP endonuclease

33. Which are the acidic amino acids
MRNA - tRNA
CTG
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Asp and Glu

34. What is variable expression and What is an example
Tryosine hydroxylase
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR

35. What does glycosylation of pro alpha chian yield and What is the structure
Glutamate
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Met - val - arg his
Procollagen - triple helix of 3 alpha collagen chains

36. What converts tyrosine to DOPA
Neg to pos
Tryosine hydroxylase
Binds to LDL receptor - mediates VLDL secretion
Foliage - small reserve in liver - eat green leaves

37. What do the single stranded binding proteins do
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Prevent strands from reannealing
Bind 30s subunit preventing attachment of aminoacyl - tRNA
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes

38. Which enzyme involved in RNA synthesis does not require a template
Thymic - parathyroid and cardiac
Dermatitis - alopecia - enteritis
Poly A polymerase - signal is AAUAA
Alpha - ketoglutarate dehydrogenase complex

39. Type II collagen
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Cartilage - hyaline - vitreous body - nucleus pulposus
Lacks glucose 6 phophatase
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

40. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
5' of the incoming nucleotide
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Terminal regions - tropocollagen
Familial hypercholesterolemia - hyperlipidemia type IIA

41. How do tetracyclines work
Neg to pos
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Bind 30s subunit preventing attachment of aminoacyl - tRNA

42. What is the energy source for tRNA actication (charging)
CAG - 4
Polycystic liver disease - berry aneurysm - mitral valve prolapse
ATP
Kidney - ears - eyes

43. What does vit B3 def result in
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Failure to track objects or develop a social smile
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
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

44. Describe the location and fxn of the Na/K ATPase
Phenytoin - MTX - and sulfonamides
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Degredation of dietary TG in small intestine
Night blindness - dry skin

45. Infection with what organism can cause B12 def
Diphyllobothrium latum
Arg - lys - his - arg is most basic - has has no charge at body pH
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Night blindness - dry skin

46. What do def in in enzymes of gluconeogenesis cause
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Disease
Hypoglycemia
Breaks down acyl - coa to acetyl coa groups in mito

47. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Read from a fixed starting point as a continuous sequence of bases
Semiconservative - continuous and discontinuous strands (okazaki fragments)

48. What rxn creates ATP
P+q = 1
Alanine
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

49. Wgat substances directly inhibit mitochondrial ATPase - causing an inc in proton gradient - no ATP because pump is stopped
Oligomycin
VLDL
Oral uridine administration
Degredation of dietary TG in small intestine

50. What is the Name and function of vit B1
Mediates extra remnant take up
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Oxalacetate