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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 makes up a nucleotide

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2. What enzyme converts adenine to AMP
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Fibrofatty replacement of muscle - cardiac myopathy
Cytosol
APRT + PRPP

3. What does NADPH oxidase deficiency result in and why
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
Collagen
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

4. What is the amino acid precuror for creatine - urea and nitric oxide
Wobble
Arginine
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Acetyl - CoA carboxylase (ACC)

5. What are the priorities for the body in fasting and starvation
HMG- CoA reductase
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Supply sufficient glucose to brain and RBCs and to preserve protein

6. Broadly - What can cause fat - soluble vitamin deficiencies
Polyneuritis - symmetrical muscle wasting
Malapsorption syndromes like sprue or CF or mineral oil intake
Liver and leafy veggies
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

7. What does the vimentin stain for
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Connective tissue
Nissl body - enzyme and NTs

8. What CETP do
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Tyrosine
Biotin
Proline and glycine (non glycosylated forms)

9. Type III collagen
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Antioxidant - protects RBCs and membrances from free radical damage
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
THFs

10. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Promotor - TATA box - and CAAT box - AT rich
Macrocytic - megaloblastic anemia - no neurologic sx - most common vit def in the US - seen in EtOH and pregs
Flagella - cilia - mitotic spindles

11. What are cyclin - CDK complexes
Must be both activated and inactivated for cell cycle to progress
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Adds 2 carbon with the help of biotin

12. Where are the secretory proteins made and N- linked oligosaccharide addtions put on proteins
Neither of 2 alleles is dominant - blood groups
RER
Inhibits the Na/K pump by binding the K side
Nonsense > missense > silent

13. What activates the pyruvate dehydrogenase complex
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Exercise: inc NAD/NADH - inc ADP - inc Ca
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
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

14. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Inhibits 50S peptidyltransferase
Protein kinase A
Lariat shape in order and remove intron precisely and join 2 exons
Oxalacetate

15. What is loss of heterozygosity and give an example
Oxidizes substrate
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
25OHD3
Alkaptonuria - may have debiliating arthralgias

16. What is the breakdown product of dopamine
HVA
Flank pain - hematuria - HTN - progressive renal failure
Transfers methyl units
Wrinkles and acne

17. 90% of ADPKD cases are due to a mutation In what gene
APKD1 on chromosome 16
Fed
Tuberous sclerosis
Night blindness - dry skin

18. What does the passage of electrons result in that when coupled to OXPHOS drives the production of ATP
B48 - AIV - CII - E
Nonsense > missense > silent
Particular sequence of DNA where replicatino begins - may be single of multiple
Proton gradient

19. 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
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Wrinkles and acne
Males are infertile due to bilateral absence of vas deferens

20. What is the result of vit B5 def
Dermatitis - enteritis - alopecia - adrenal insuff
Tryosine hydroxylase
Intermediate filaments
MRNA

21. in a 100 meter sprint Where does energy come from
Stored ATP - creatine phosphate - anaerobic glycolysis
CAG
Blood - bone marrown - amniotic fluid - placental tissue
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

22. developmental delay - gargoylism - airway obstruction - corneal clouding - hepatosplenomegaly
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Schwann cells - lens - retina - kidneys
Mediates extra remnant take up

23. What does a northern blot use as its sample
Rb and p53
Infection - free radicals generated by inflammatory response
Protein
RNA

24. What does cytokeratin stain for
Epithelial cells
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
Debranching enzyme
Creat a nick in the helix to relieave supercoils created during replication

25. What are the findings in orotic aciduria
Essential fructosuria - fructokinase AR
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Marasmus - muscle wasting

26. What initiates protein synthesis
RNA poly II
FAP
Must be both activated and inactivated for cell cycle to progress
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex

27. What produces NADPH
Alpha 1 -4 glucosidase
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Peroxide
HMP shunt

28. How do fluoroquinolones work
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Enhancers
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Makes RNA primer on which DNA poly III can initiate replication

29. What are the findings with homocystinuria and What amino acid is needs to be supplemented
Inhibits RNA polymerase II - found in death cap mushrooms
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Conversion of NE to epi
Palate - facial and cardiac defects

30. What is the amino acid precursor for GABA and glutathione
If pt inherits or develops a mutation in a tumor suppresor gene - the complementary allele must be deleted/mutated before cancer develops - not true of oncogenes - retinoblastoma
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Glutamate

31. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Phenylethamolamine N methyl transferase
Specific glycosylases - AP endonuclease
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)

32. What does a phosphatase do
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Removes phosphate group from substrate
Arg - lys - his - arg is most basic - has has no charge at body pH

33. What does osteogenesis imperfecta causes and why
III - joint dislocation - anuerysms - organ rupture
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Core proteins
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

34. What does a dehydrogenase do
Phosphofructokinase 1
Oxidizes substrate
After citruline
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs

35. How do odd chain fatty acids participate in gluconeogenesis
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Phosphorylation - glycosylation - hydroxylation
SNP

36. What happens on the nonoxidative arm of the HMP shunt and What is the key enzyme and cofactor
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
Liver - also in kidney and gut epithelium
Neither of 2 alleles is dominant - blood groups
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

37. What is the pathway in the fed state leading to dec FBPase -2 and inc PFK-2
Inc insulin - dec cAMP - dec PKA
P2 +2pq+ = 1
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

38. What substance in egg whites binds biotin
Polyneuritis - symmetrical muscle wasting
Avidin
Seals.
NADH - NADPH - FADH2

39. What substances induce phosphofructokinase
Active secretion in lungs and GI - reabsorbs in skin
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE
APKD1 on chromosome 16
AMP - fructose 2 -6 BP

40. What does the mutation in the gene cause in protein synthesis
Abnormal protein folding - degradation before reaching cell surface
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Cyclin dependent kinases;constitutive and inactive
Inc dicarboxylic acids - dec in glucose and ketones

41. What makes up a nucleoside
DsRNA promotes degradation of target mRNA knocking down gene expression
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Connective tissue
Base + ribose

42. What are the symptoms of vit A excess
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
FAP
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Glucose 6 phosphatase

43. What does the primary transcript combine with to form the spliceosome
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Males are infertile due to bilateral absence of vas deferens
SnRNPs and other proteins
Fasting

44. Which amino acids are elastin rich in
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Proline and glycine (non glycosylated forms)
Leu - lys
NAD+

45. What causes Hartnup's disease
Infection - free radicals generated by inflammatory response
Purines= A - G pyrimidine = C - T (U)
AR disorder characterized by defective neutral amino acid transporte on renal and intestinal epith cells
Night blindness - dry skin

46. What is locus heterogeneity and give an example
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
32 - malate aspartate shuttle

47. What are the results of CF on male fertility
Males are infertile due to bilateral absence of vas deferens
Fasting
Oxidative is irreversible
Cre - lox system

48. What is the most abundant protein in the body
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Collagen
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
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria

49. What is I cell disease
Neurons
Glucose 6 phosphatase
CAG - 4
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes

50. What is axonemal dynein
P2 +2pq+ = 1
IMP precursor
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets
Defect in fibrillin