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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. In eukaryotes - What does RNA poly II make
Wernicke - korsakoff - dry and wet beriberi
MRNA
Phenylalanine
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation

2. What happens in vit K def
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
Tuberous sclerosis
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea

3. What do the single stranded binding proteins do
Prevent strands from reannealing
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
Acetly- CoA - CO2 - NADH
SAM

4. What does the deletion of the dystrophin gene lead to...
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Males are infertile due to bilateral absence of vas deferens
Accelearted muscle breakdown

5. What are the characteristics of prader willi syndrome How does it occur
32 - malate aspartate shuttle
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
ATP

6. In eukaryotes - What does RNA poly I make
Dopamine beta hydroxylase
Fibroblast
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
RRNA

7. what gene is implicated in fragile X syndrome - and What is the mutation
Change resulting in early stop codon
4 under the floor
FMR1 gene - methylation - associated with chromosomal breakage
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

8. What does the ELISA test for
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
APKD1 on chromosome 16
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
Neural tube

9. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Dec DNA - dec lymphos leads to SCID
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Proline and glycine (non glycosylated forms)
HGPRT - defective purine salvage - excess uric acid production

10. Which step in the de novo purine and pyrimidine synthesis pathway requires just aspartate
Orotic acid to UMP
Von Gierke's - Pompe - Cori - McArdle
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Alpha 1 -6 and alpha 1 -4

11. Who typically has lactase def
Dec DNA - dec lymphos leads to SCID
Acetyl - CoA carboxylase (ACC)
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
African Americans and Asians

12. What rxn creates ATP
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
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Liver - also in kidney and gut epithelium

13. What is heteroplasmy
Dec methionine - inc cystiene - inc B12/folate
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Antigen - antibody reactivity - can look for antigen or antibody in patients blood
High output cardiac failure - dilated cardiomyopathy - edema

14. What are bite cells and when do you see them
Result from phagocytic removal of heinz bodies my macs - G6PD def
B12 and folate
Activates LCAT
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1

15. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Wobble
Same as sprint + OXPHOS
II - VII - IX - X (1972) protein C and S
IDL

16. 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
Neurofibromatosis type 1 (von Recklinghausens disease)
Acetyl - CoA to malonyl - CoA (2C to 3C)
Inhibits the Na/K pump by binding the K side

17. What is the main source of folate
Tall with long extremeties - pectus excavatum - hyperextensive joints - arachnodactyly
OTC has hyperammonemia - orotic aciduira does not
Foliage - small reserve in liver - eat green leaves
FISH

18. What is the defect in I- hyperchylomicronemia
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Removal of N or C termal propeptides from zymogens to generate mature proteins
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Glucose 6 phosphatase

19. Severe fasting hypoglycemia - inc glycogen storage in liver - inc blood lactate - hepatomegaly - dz and def enzyme
Attachment of ubiquitin to defective proteins tag them for breakdown
RER
Unwinds DNA template at replcation fork
Von gierkes - glucose 6 phosphatase

20. What do def in in enzymes of gluconeogenesis cause
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
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
Glycogen and FFA oxidation; glucose conserved for final sprinting
Hypoglycemia

21. Which anti gout drugs work on microtubules
Alkaptonuria - may have debiliating arthralgias
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Colchicine

22. How does patients present with ADPKD
Flank pain - hematuria - HTN - progressive renal failure
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Inc Cl - in sweat
B48 - AIV - CII - E

23. depression - progressive dementia - choreiform movements - caudate atrophy and dec levels of GABA and ACH in the brain
Huntingtons
TRNA
CarTWOlage
UGA - UAA and UAG

24. How many rings do purines have
Particular sequence of DNA where replicatino begins - may be single of multiple
Medial dorsal nucleus of thalamus - mamillary bodies
Rb and p53
2 rings

25. What is the Name and function of vit B1
Schwann cells - lens - retina - kidneys
Acetyl - CoA
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Adds an inorganic phosphate onto substrate without using ATP

26. pyruvate carboxylase catalyzes what rxn
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Pyruvate to oxaloacetate (3C to 4C)
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Binds to LDL receptor - mediates VLDL secretion

27. For eukaryotes - Where does replication begin?
Terminal regions - tropocollagen
Consesus sequenec of base pairs
RRNA
Degredation of dietary TG in small intestine

28. What does a dehydrogenase do
1 kind with multiple subunits
Oxidizes substrate
Dermatitis - glossitis - and diarrhea
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

29. What two amino acids are required druing periods of growth and why
Arginine
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Arg and his inc in histones Which bind negatively charged DNA
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol

30. What is the defect in II A familial hypercholesterolemia
Zero
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse

31. How many ATP are produced by anearobic glycolysis per molecule of glucose
ATP
Two
Stored ATP - creatine phosphate - anaerobic glycolysis
IMP precursor

32. What defects characterize DiGeorge syndrome
Thymic - parathyroid and cardiac
Methionine encode by only 1 codon (AUG)
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Diphyllobothrium latum

33. What is the exception to genetic redundancy
Methionine encode by only 1 codon (AUG)
Schilling test
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Inc dicarboxylic acids - dec in glucose and ketones

34. What are ketone bodies made from - where are they metabolized and how are they excreted
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
75 to 90 - cloverleaf
Glucose - 2Pi - 2ADP - 2NAD+
MEN - 2A and 2B with ret gene

35. What polar group does guanine have - and what non polar group does thymine have
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
Ketone - methyl
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Lysine and arginine

36. What happens in a B12 def
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Lacks glucose 6 phophatase
Proline and lysine - vit C
Targets the proteins for lysosome

37. What is the activated carrier for electrons
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Adds 2 carbon with the help of biotin
Glycine - aspartate - glutamine
NADH - NADPH - FADH2

38. What catacholamine step is SAM required for
Two
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Conversion of NE to epi
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

39. What is anticipation and give an example
APRT + PRPP
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Medial dorsal nucleus of thalamus - mamillary bodies
Pyruvate to oxaloacetate (3C to 4C)

40. What do neurofilaments stain for
Neurons
Biotin
UGA - UAA and UAG
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

41. What is regeneration of methionine depedent on...
Unmethylated - newly synthesized - HNPCC
B12 and folate
Inc CPK and muscle biopsy
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

42. Which aspect of the spliceosome do patients with lupus make antibodies against
Night blindness - dry skin
SnRNPs
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Stop codon is recognized by release factor - and completed protein is released from ribosome

43. How does ethanol induce hypoglycemia
Phenylketones in urine
IMP precursor
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
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

44. What causes biotin def
HMG- CoA synthase
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
Change resulting in early stop codon
Antibiotic use or excessive ingestion of raw eggs

45. What converts DOPA to dopamine
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Degradation of TG remaining in IDL
RNA poly II
Dopa decarboxylase

46. What does the start codon code for in eukaryotes and prokaryotes
Robertsonian translocation and mosaicism
Hypoglycemia
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
Eu - methionine - pro - formyl - methionine

47. What is the RER called in neurons and What is made there
Nissl body - enzyme and NTs
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Change resulting in early stop codon
Phosphofructokinase 1

48. What is the longest time of RNA and shortest
FAP
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Attachment of ubiquitin to defective proteins tag them for breakdown
MRNA - tRNA

49. Wgat substances directly inhibit mitochondrial ATPase - causing an inc in proton gradient - no ATP because pump is stopped
Oligomycin
30 - glycerol -3- phosphate shuttle
Flagella - cilia - mitotic spindles
Oral uridine administration

50. Describe the location and fxn of the Na/K ATPase
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Particular sequence of DNA where replicatino begins - may be single of multiple
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
Sons of heterozygous mothers have 1/2 half chance of being affected - no male to male transmission - and often more severe in males - heterozygous females may be affected