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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 else can phosphoylate phosphorylase kinase
Base + ribose + phosphate (3' -5') phosphodiester bond
Ca/calmodulin in muscle to coordinate with muscle activity
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Fasting

2. What is the defect in fructose intolerance and What does it cause
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
CarTWOlage
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
VMA

3. Which are the basic amino acids
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns
Arg - lys - his - arg is most basic - has has no charge at body pH
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

4. What does the primary transcript combine with to form the spliceosome
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
SNP
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
SnRNPs and other proteins

5. What does a southern blot use as its sample
DNA
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
30 - 50 - 70
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

6. ADPKD is associated with What additional conditions
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Attachment of ubiquitin to defective proteins tag them for breakdown
Keep glutathione reduced so it can detoxify free radicals and peroxides
Glycine

7. What are the functinos of vitamin A
Cri du chat
Binds to LDL receptor - mediates VLDL secretion
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
DsRNA promotes degradation of target mRNA knocking down gene expression

8. What do B- complex vitamin deficiencies often result in
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Glycogen synthase
Dermatitis - glossitis - and diarrhea
3' end (with CCA)

9. What is variable expression and What is an example
Lysine and leucine
Glucose - 2Pi - 2ADP - 2NAD+
Oxidative and nonoxidative - no ATP produced or used
Nature and severity of phenotype vary from 1 individual to another - NF type 1

10. What is the activated carrier for Co2
Acetyl - CoA to malonyl - CoA (2C to 3C)
Biotin
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
LDL

11. Where are the secretory proteins made and N- linked oligosaccharide addtions put on proteins
Polycystic liver disease - berry aneurysm - mitral valve prolapse
RER
Malabsorption and steatorrhea (ADEK)
Schilling test

12. What are cyclins
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
SnRNPs
Fructose 1 -6 bisphosphate
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

13. Where do you find elastin and What does it do
Peroxide
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
MEN - 2A and 2B with ret gene
Dopamine beta hydroxylase

14. What are the symptoms of vit A def
TRNA
Reads usual codon but inserts wrong AA
Night blindness - dry skin
THFs

15. trinucleotide repeat for huntingtons
ATP hyrdolysis couple to energetically unfavorable rxns
CAG
Sulfation
Carnitine acyltransferase I

16. How do macrolides and clindamycin work
Binds 50S - blocking translocation
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
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Two

17. What causes B12 def
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
SNP
Paclitaxel
Malabsorption (sprue - enteritis) lack of intrinsic factor from pernicious anemia - gastric bypass surgery or absence of terminal ileum as in Crohns

18. What do albinism - ARPKD - CF - glycogen storage diseases - hemochromatosis - mucopolysaccharidoses (except Hunters) PKU - sickle cell - sphingolipodoses (except Fabrys) thalassemias have in common
Autosomal recessive diseases
Specific glycosylases - AP endonuclease
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells

19. What are the clinical features of I cell diesase
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
CarTWOlage
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)

20. What is the RDE of cholesterol synthesis
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
SnRNPs
Type II
HMG- CoA reductase

21. characterize autosomal recessive inheritance
In ER - glucose 6- P to glucose
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
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step
Phenylethamolamine N methyl transferase

22. What is the energy source after day 3 of starvation
Initiate chains
Debranching enzyme
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
P2 +2pq+ = 1

23. What substance in egg whites binds biotin
Proton gradient
Avidin
Unwinds DNA template at replcation fork
4 under the floor

24. What is linkage disequilibrium
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
African Americans and Asians

25. What causes biotin def
Scrutinizes - hydrolyzes the bond
Antibiotic use or excessive ingestion of raw eggs
Muscle
Stop codon is recognized by release factor - and completed protein is released from ribosome

26. caf
Acetly- CoA - CO2 - NADH
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
Neurofibromatosis type 1 (von Recklinghausens disease)
APKD1 on chromosome 16

27. What is the RDE of gluconeogenesis
Terminal regions - tropocollagen
Fructose 1 -6 bisphosphate
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

28. Describe the structure of cilia
9+2 arrangement of microtubules
Epithelial cells
Degradation of TG remaining in IDL
Poly A polymerase - signal is AAUAA

29. How do labile celss grow and regenerate and What are examples
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Oxidative is irreversible
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins

30. Give an example of a mitochondrial inherited disease
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
Glutamate

31. Giving folate during early pregnancy is important to prevent what birth defects
By inhibiting formation of the initiation complex and cause misreading of mRNA
Neural tube
Chylomicrons
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

32. In the chromatin structure - which histones form the octamer - and which ties the nucleosome beads together in a string?
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
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

33. What is the results of vit B1 def
Schwann cells - lens - retina - kidneys
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
AR
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first

34. What enzyme converts adenine to AMP
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
1 kind with multiple subunits
Scrutinizes - hydrolyzes the bond
APRT + PRPP

35. What are the symptoms of vit A excess
Pyruvate to oxaloacetate (3C to 4C)
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
NH2-(C=O) - NH2 one NH2 from ammonia the C=O from CO2 - and the other NH2 from aspartate
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

36. What is the hardy weinberg allele prevalence
P+q = 1
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Vincritsine/vinblastine
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

37. What are the names and sources of the two types of vit D found in nature
B48 - AIV - CII - E
Carbomoyl phosphate synthetase I
Nonsense > missense > silent
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

38. What amino acid makes up most of the octamer
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Facial flushing
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Lysine and arginine

39. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Dopamine beta hydroxylase
Robertsonian translocation and mosaicism
Hereditary spherocytosis
Malabsorption and steatorrhea (ADEK)

40. In eukaryotes - What does RNA poly II make
MRNA - tRNA
MRNA
Assistance of upper extremities to stand up
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy

41. What does degenerate/rundant genetic code refer to...
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Neural tube
Liver - also in kidney and gut epithelium
More than 1 codon may code for the same amino acid

42. Which step in the de novo purine and pyrimidine synthesis pathway requires just aspartate
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora
Inc dicarboxylic acids - dec in glucose and ketones
Vit K antagonist
Orotic acid to UMP

43. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
Tuberous sclerosis
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

44. What do DNA topoisomerases do
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Creat a nick in the helix to relieave supercoils created during replication
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Paclitaxel

45. What are the findings in orotic aciduria
Sulfation
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Immotile cilia due to dynein arm defect - male and femail infertile - bronchiectasis - recurrent sinusitis - associated with situs inversus

46. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
IDL
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

47. What ribosomes do eukaryotes have
Biotin
40 - 60 - 80
Grows slowly - collapses quickly
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia

48. What does vit E def cause
Defect in fibrillin
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Connective tissue
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

49. What is the order of severity for the different types of mutations
Inc dicarboxylic acids - dec in glucose and ketones
Tryosine hydroxylase
Nonsense > missense > silent
Cofactor for LPL

50. What are purines made from
Fibroblast
IMP precursor
HDL
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes