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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 cells are rich in smooth ER
By inhibiting formation of the initiation complex and cause misreading of mRNA
G6PD
Liver hepatocytes and steroid producing cells of the adrenal cortex
Inc insulin - dec cAMP - dec PKA

2. What does NADPH oxidase deficiency result in and why
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
DTMP
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

3. What is the RDE of de novo purine synthesis
Glutamine PRPP amidotransferase
Debranching enzyme
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Wobble

4. What does amino acid catabolsim results in the formation of what?
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Von hippel lindau - 3
Result from phagocytic removal of heinz bodies my macs - G6PD def

5. What does biotin def cause
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Orotic acid to UMP
32 - malate aspartate shuttle
Dermatitis - alopecia - enteritis

6. cytoskeletal elements associated with vimenentin - desmin - cytokeratin - glial fibrillary acid protiens (GFAP) - neurofilaments
Intermediate filaments
AMP - fructose 2 -6 BP
RRNA
Base + ribose + phosphate (3' -5') phosphodiester bond

7. What are the findings in orotic aciduria
Avidin
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Males are infertile due to bilateral absence of vas deferens

8. What does pancreatic lipase do
Marasmus - muscle wasting
CAG
Degredation of dietary TG in small intestine
Mitochondria

9. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Removes phosphate group from substrate
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Von Gierke's - Pompe - Cori - McArdle

10. What is axonemal dynein
Unwinds DNA template at replcation fork
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Glutamine PRPP amidotransferase
Malonyl coa

11. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Each codon specifies only 1 amino acid
ATP hyrdolysis couple to energetically unfavorable rxns
Huntingtons
Silencers

12. facial lesions - hypopigmented 'ash leaf spots -' cortical and retinal hamartomas - seizures - mental retardation - renal cysts - renal angiomyolipomas - cardiac rhabdomyomas - inc risk of astrocytomas
TRNA
Tuberous sclerosis
Arg and his inc in histones Which bind negatively charged DNA
Microarrays

13. What does SAM do
LDL
Transfers methyl units
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

14. What are purines made from
Must be both activated and inactivated for cell cycle to progress
4 under the floor
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
IMP precursor

15. What part of the pre mRNA contains the actual genetic information coding for protein
Not all individuals with a mutant genotype show the mutant phenotype
Exons
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis

16. Type IV BM
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
4 under the floor
Initiate chains
P+q = 1

17. What happens in vit K def
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Neurons
Change resulting in early stop codon
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

18. What is a missense mutation
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Changed AA (convservative - new AA is similar in chemical structure)
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
VLDL

19. cytoskeletal elements associated with cilia - flagella - mitotic spindle - neurones and centrioles
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Microtubules
Inhibits the Na/K pump by binding the K side
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

20. What do B- complex vitamin deficiencies often result in
Pyruvate - NAD+ - CoA
Dermatitis - glossitis - and diarrhea
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

21. How is orotic aciduria inherited
Removes phosphate group from substrate
4 under the floor
AR
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

22. What polar group does guanine have - and what non polar group does thymine have
Removes phosphate group from substrate
Ketone - methyl
TRNA
Chronic granulomatous disease - no respiatory burst - no formatino of ROS

23. What two proteins make up microtubules and how are they arranged
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Alpha and beta tubulin - dimers have two GTP bound
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
Marfans

24. What are the results of pancreatic insuff in CF
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Malabsorption and steatorrhea (ADEK)
3' end (with CCA)
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin

25. What is the initial transcript called and What is the capped and tailed transcript called
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Q -
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
MRNA

26. What is NADPH used for
Anabolic processes as a supply of reducing equivalents
Carnitine acyltransferase I
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Rotenone - CN- - antimycin A - CO

27. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
Reads usual codon but inserts wrong AA
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Fibrofatty replacement of muscle - cardiac myopathy

28. antbiotic controlled promoter to induciblly manipulate genes at specific developmental points
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Cre - lox system
NADPH
O- oligosaccharaides

29. delivers hepatic TGs to peripheral tissue - secreted by liver
VLDL
Inc CPK and muscle biopsy
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
APKD1 on chromosome 16

30. What can vit B3 be used to treat
ATP and alanine
Hyperlipidemia
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Collagen

31. What does glycosylation of pro alpha chian yield and What is the structure
Dermatitis - alopecia - enteritis
Procollagen - triple helix of 3 alpha collagen chains
CG- 3 > AT-2 - More CG content - melting point goes up
Fructose 1 -6 bisphosphate

32. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Malonyl coa
Actin and myosin
Pyruvate - NAD+ - CoA

33. Type II cartilage
DNA
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Post to neg
CarTWOlage

34. Delivers dietary TGs to peripheral tissues - delivers cholesterol to liver in the form of remnants - mostly depleted of TGs - secreted by intestinal epith cells
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Chylomicrons
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

35. What inhibits the carnitine shuttle
Malonyl coa
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Malabsorption and steatorrhea (ADEK)
AMP - fructose 2 -6 BP

36. What substances directly inhibit electron transport chain
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Rotenone - CN- - antimycin A - CO
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Phenylethamolamine N methyl transferase

37. Do balanced translocations cause abnl phenotype
N to C
No
Phenylalanine
One

38. What is the TX for CF and What does it do
Myeloperoxidase
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Transfers methyl units

39. what disease can cause pellagra
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Arg - lys - his - arg is most basic - has has no charge at body pH
Alanine
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

40. How do glucagon/epi lead to glycogenolysis
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
2 -4 DNP - aspirin
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
Core proteins

41. What substance inside the cell reduces glutatione
Attachment of ubiquitin to defective proteins tag them for breakdown
Sulfation
Active secretion in lungs and GI - reabsorbs in skin
NADPH

42. What catacholamine step is SAM required for
Activates LCAT
Conversion of NE to epi
B48 - AIV - CII - E
Unwinds DNA template at replcation fork

43. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
3' end (with CCA)
Hereditary spherocytosis
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs

44. What substances inhibit phosphofructokinase -1
Reads usual codon but inserts wrong AA
Robertsonian translocation and mosaicism
ATP - citrate
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

45. What does a carboxylase do
LCAT (lecithin cholesterol acyltransferase)
Adds 2 carbon with the help of biotin
Activates LCAT
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

46. What is the defect in II A familial hypercholesterolemia
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Degredation of dietary TG in small intestine
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle

47. What is the target of the 3' hydroxyl attack
SnRNPs
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
The triphosphate bond

48. peripheral neuropathy - developmental delay - optic atrophy - glopoid cells
X linked frame shif mutation
Krabbes - galactocerebrosidase - galactocerebroside - AR
IDL
Flagella - cilia - mitotic spindles

49. Type I bone
BOne
Dec DNA - dec lymphos leads to SCID
Phenylalanine
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS

50. What happens with wet beriberi
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Glycine
High output cardiac failure - dilated cardiomyopathy - edema