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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 acetyl - CoA become before becoming palmitate
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
1 -25 OH2 D3 = calcitriol
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Breaks down acyl - coa to acetyl coa groups in mito

2. What are the 4 assumption of the Hardy Weinberg law
Alpha and beta tubulin - dimers have two GTP bound
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Only processed RNA
DTMP

3. trinucleotide repeat for huntingtons
Marfans
CAG
Comlex II
Mitochondria

4. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
Acetyl - CoA
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Pseudomonas and s aureus
HMG- CoA synthase

5. Mild Hurlurs + aggressive behavior no corneal clouding
ATP - citrate
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR

6. What is the activated carrier for Acyl
Coenzyme A - lipoamide
HGPRT - defective purine salvage - excess uric acid production
25OHD3
Protein kinase A

7. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Seals.
Glucose 6 phosphate dehydrogenase (G6PD)

8. What is the main source of folate
Glycogenolysis to form glucose
Q -
Phosphorylation - glycosylation - hydroxylation
Foliage - small reserve in liver - eat green leaves

9. What is used to diagnose muscular dystrophies
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Inc CPK and muscle biopsy
Ketone - methyl
Neural tube

10. Which are the basic amino acids
Particular sequence of DNA where replicatino begins - may be single of multiple
MRNA
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Arg - lys - his - arg is most basic - has has no charge at body pH

11. What does desmin stain for
Muscle
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Mental retardation - flat facies - prominent epicanthal folds - simian crease - gap between 1st 2 toes - duodenal atresia - congenital heart disease (ASD) - inc risk of All and Alzheimers
B100

12. ADPKD is associated with What additional conditions
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Dec methionine - inc cystiene - inc B12/folate
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Phenytoin - MTX - and sulfonamides

13. What does PURe As Gold and CUT The Py stand for
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Actin and myosin
Purines= A - G pyrimidine = C - T (U)
TTP

14. What collagen type is most frequently affected in ehlers danlos and What are common complications
Adds 2 carbon with the help of biotin
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus
Unmethylated - newly synthesized - HNPCC
III - joint dislocation - anuerysms - organ rupture

15. What induces pyruvate kinase
Glycine - aspartate - glutamine
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Phenylethamolamine N methyl transferase
F16BP

16. What do neurofilaments stain for
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Neurons
Phenylalanine hydroxylase

17. What is the function of Zinc
Von Gierke's - Pompe - Cori - McArdle
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Griseofulvin
Adds an inorganic phosphate onto substrate without using ATP

18. What are the clinical features of I cell diesase
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Glycogen phosphorylase
Glucose -6 phosphate
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood

19. What is the amino acid precursor for GABA and glutathione
Flagella - cilia - mitotic spindles
Glutamate
Carnitine acyltransferase I
Adds an inorganic phosphate onto substrate without using ATP

20. What are pyrimidines made from
Covalent cross - linking by lysyl oxidase to make collagen fibrils
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
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
Orotate precursor - with PRPP added later

21. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Chylomicrons
Avidin

22. RNA poly can't proofread - but What can it do
Initiate chains
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Medial dorsal nucleus of thalamus - mamillary bodies
Adds 2 carbon with the help of biotin

23. What is the activated carrier for 1 carbon units
Tuberous sclerosis
THFs
Basement membrane or basal lamina
5' to 3'

24. What drugs can cause folate def
Phenytoin - MTX - and sulfonamides
B-100 - CII and E
Facial flushing
CTG

25. What is the RDE of ketogenesis
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
HMG- CoA synthase
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Pyruvate to oxaloacetate (3C to 4C)

26. For eukaryotes - Where does replication begin?
Consesus sequenec of base pairs
Pyruvate - NAD+ - CoA
Oligomycin
Read from a fixed starting point as a continuous sequence of bases

27. What does hepatic TG lipase do
Scrutinizes - hydrolyzes the bond
Paclitaxel
Degradation of TG remaining in IDL
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

28. Describe the replication fork
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Microarrays

29. What lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
Wobble
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Scrutinizes - hydrolyzes the bond
PCR - denaturation - annealing - elongation

30. several distinct syndromes characterized by familial tumors of endocrine glands including pancreas - parathyroid - pituitary - thryoid and adrenal medulla - disorders and gene association
Lacks glucose 6 phophatase
Inc Cl - in sweat
MEN - 2A and 2B with ret gene
Infection - free radicals generated by inflammatory response

31. What does a mischarge tRNA do
Alpha 1 -4 glucosidase
Reads usual codon but inserts wrong AA
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
Two

32. What are the findings in Down's syndrome
Seals.
Mental retardation - flat facies - prominent epicanthal folds - simian crease - gap between 1st 2 toes - duodenal atresia - congenital heart disease (ASD) - inc risk of All and Alzheimers
HMG- CoA (HMG- CoA to mevalonate
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase

33. What happens with dry beriberi
Two
Polyneuritis - symmetrical muscle wasting
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
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

34. What are the glucogenic essential amino acids
Met - val - arg his
No - its non homologous
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Sucrose = glucose + fructose - lactose = glucose + galactose

35. What is the wernicke - korsakoff clinical picture
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
RNA poly II
Glucose 6 phosphate dehydrogenase (G6PD)
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss

36. 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
Alkaptonuria - may have debiliating arthralgias
Deamination
B6
By inhibiting formation of the initiation complex and cause misreading of mRNA

37. What are purines made from
IMP precursor
UDP glucose pyrophosphorylase
Neurons
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra

38. What converts dopamine to NE
Dopamine beta hydroxylase
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
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
Familial hypercholesterolemia - hyperlipidemia type IIA

39. What is the TX for hyper ammonemia
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Facial flushing
Mebendazole/thiabendazole

40. What is RNAi used for
DsRNA promotes degradation of target mRNA knocking down gene expression
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Fed
Von gierkes - glucose 6 phosphatase

41. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
BOne
Inhibits the Na/K pump by binding the K side
Marasmus - muscle wasting
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

42. Where are cytosolic and organellar proteins made
Free ribosomes
PMNs
25OHD3
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

43. Which RNA poly opens DNA at promotor site
30 - glycerol -3- phosphate shuttle
Adenosine to inosine
RNA poly II
Schwann cells - lens - retina - kidneys

44. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Cre - lox system
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
Acetyl - CoA carboxylase (ACC)

45. What is a silent mutation
Same AA - often base change in 3rd position of codon (tRNA wobble)
Nature and severity of phenotype vary from 1 individual to another - NF type 1
NF2 on chromosome 22
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

46. How many nucTIDEs is a tRNA and What does the secondary sturcture form
Protein
75 to 90 - cloverleaf
B-100 - CII and E
Fructose 1 -6 bisphosphate

47. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
Type II
Carbomoyl phosphate synthetase I
Fructose 1 -6 bisphosphate
SAM

48. How does abetalipoproteinemia present and What is the defect
Glycogen phosphorylase
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
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

49. What does hartnups disease cause
Alpha and beta tubulin - dimers have two GTP bound
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Inc dicarboxylic acids - dec in glucose and ketones
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

50. The pyruvate dehydrogenase complex serves In what reaction: products
Nine
Adds an inorganic phosphate onto substrate without using ATP
Acetly- CoA - CO2 - NADH
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins