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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. Which carbon bears the triphosphate and the energy source for bond formation

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2. pyruvate carboxylase catalyzes what rxn
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Pyruvate to oxaloacetate (3C to 4C)
Attachment of ubiquitin to defective proteins tag them for breakdown
III - joint dislocation - anuerysms - organ rupture

3. Type I bone
Acetyl - CoA
BOne
VLDL
Each codon specifies only 1 amino acid

4. What is codominance and give an example
Zero
Q -
Neither of 2 alleles is dominant - blood groups
Acetoacetate and beta hydroxybutyrate

5. What do neurofilaments stain for
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Skin
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Neurons

6. How do aminoglycosides work
By inhibiting formation of the initiation complex and cause misreading of mRNA
Inc CPK and muscle biopsy
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Hereditary spherocytosis

7. What is the RDE of gluconeogenesis
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Fructose 1 -6 bisphosphate
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Degredation of dietary TG in small intestine

8. This is the site where negative regulators bind
Assistance of upper extremities to stand up
Transfers methyl units
Silencers
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

9. What metabolic rxns occur in the mitochondria
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
NADPH
Acetoacetate and beta hydroxybutyrate
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

10. caf
4 under the floor
Neurofibromatosis type 1 (von Recklinghausens disease)
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
B100

11. What feedback inhibits hexokinase
Glucose -6 phosphate
Nine
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Glutamate

12. What is locus heterogeneity and give an example
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Silencers
Glucose -6 phosphate

13. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Muscle
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE
Familial hypercholesterolemia - hyperlipidemia type IIA

14. Where is pyruvate carboxylase found - What does it do - What does it require amd What activates it
Binds 50S - blocking translocation
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

15. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
CAG - 4
Cri du chat

16. What is the treatment for dec affinity of cystathionine synthase for pyroxidal phosphate
Inc vit B6
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Males are infertile due to bilateral absence of vas deferens
PMNs

17. What does a western blot use for its sample
G6PD
Protein
75 to 90 - cloverleaf
Neimann - pick - sphingomyelinase - sphingomyelin - AR

18. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
Base + ribose + phosphate (3' -5') phosphodiester bond
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Protein kinase A
Mediates extra remnant take up

19. What does commaless - nonoverlapping genetic code refer to...
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
F16BP
Read from a fixed starting point as a continuous sequence of bases
Schwann cells - lens - retina - kidneys

20. What are the water soluble vitamins - which ones are stored
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
EtOH dehydrogenase and acetaldehyde dehydrogenase
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
Keep glutathione reduced so it can detoxify free radicals and peroxides

21. trinucleotide repeat fo myotonic dystrophy
APC on chromosome 5
Proline and glycine (non glycosylated forms)
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
CTG

22. How do permanent cells grow and regenerate and What are examples of permanent cells
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
RNA
Nissl body - enzyme and NTs

23. How does warfarin work
Paclitaxel
Vit K antagonist
Palate - facial and cardiac defects
Dermatitis - enteritis - alopecia - adrenal insuff

24. What is the energy source for translocation
GTP
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
MEN - 2A and 2B with ret gene
LCAT (lecithin cholesterol acyltransferase)

25. In which direction is protein synthesized
UDP glucose pyrophosphorylase
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
N to C
Dopa decarboxylase

26. What two proteins make up microtubules and how are they arranged
Alpha and beta tubulin - dimers have two GTP bound
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
SAM

27. What is the function of biotin
Cofactor of carboxyltion enzymes: pyruvate carboxylase - acetate - CoA carboxylase - and propionyl - CoA carboxylase
Stop codon is recognized by release factor - and completed protein is released from ribosome
Achondroplasia
Schwann cells - lens - retina - kidneys

28. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Actin and myosin
Glucose -6 phosphate
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
ATP

29. What does helicase do
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Unwinds DNA template at replcation fork
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
RRNA

30. What is used to diagnose muscular dystrophies
Inc CPK and muscle biopsy
G6PD
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
Liver and leafy veggies

31. What components come together to make S- adenosyl methionine
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Mediates chylomicron secretion
Alpha 1 -6 and alpha 1 -4
ATP and methionine

32. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
Zero
B-100 - CII and E
Krabbes - galactocerebrosidase - galactocerebroside - AR
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US

33. characterize mitochondrial inheritance
Transmitted only through mother - all offspring of affected females may show signs of disease
Oxidized hemoglobin precipiated within RBCs
Removal of N or C termal propeptides from zymogens to generate mature proteins
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels

34. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Tyrosine
Sucrose = glucose + fructose - lactose = glucose + galactose
Citrate - acetyl coa from mito to cyto
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

35. What are cyclin - CDK complexes
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Must be both activated and inactivated for cell cycle to progress
Conversion of NE to epi
Degredation of TG circulating in chylomicrons and VLDLs

36. In eukaryotes - What does RNA poly I make
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
RRNA
Kwashiorkor - small child with swollen belly

37. What substances directly inhibit electron transport chain
Polyneuritis - symmetrical muscle wasting
L form
X linked frame shif mutation
Rotenone - CN- - antimycin A - CO

38. What is the name is fxn of vit B3
THFs
Niacin - constituent of NAD and NADP - derived from tryptophan
Differences in phenotype depend on whether the mutation is of maternal or paternal origin - prader - willi and angelman's syndrome
Degredation of dietary TG in small intestine

39. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Niacin - constituent of NAD and NADP - derived from tryptophan
Peroxide
P+q = 1
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase

40. What is proteasomal degredation
Attachment of ubiquitin to defective proteins tag them for breakdown
Promotor - TATA box - and CAAT box - AT rich
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
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

41. What is the TX for PKU
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
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Binds 50S - blocking translocation

42. What defects characterize velocardiofacial syndrome
After day 1
Palate - facial and cardiac defects
9+2 arrangement of microtubules
Neither of 2 alleles is dominant - blood groups

43. What is the initial transcript called and What is the capped and tailed transcript called
Procollagen - triple helix of 3 alpha collagen chains
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
AR
Cleft palate - cardiac abnl - pregs test

44. What 3 syndromes are associated with vit B1 def
Wernicke - korsakoff - dry and wet beriberi
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Epithelial cells
Blood - bone marrown - amniotic fluid - placental tissue

45. What does glycosylation of pro alpha chian yield and What is the structure
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
Procollagen - triple helix of 3 alpha collagen chains
Dopamine beta hydroxylase
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis

46. What is the defectin IV - hypertriglyceridemia
Sulfation
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Ile - phe - thr - trp

47. What rxn creates ATP
Accelearted muscle breakdown
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
P2 +2pq+ = 1
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

48. How many ATP are created by aerobic metobolism of glucose in muslce via what shuttle
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
30 - glycerol -3- phosphate shuttle
CGG

49. What does a defective Cl channel do
Schilling test
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR

50. What are the reactants for glycolysis
Glucose - 2Pi - 2ADP - 2NAD+
Dec methionine - inc cystiene - inc B12/folate
THFs
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly