Test your basic knowledge |

Biochemistry

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What is the amino acid precuros for niacin and serotonin/melatonin
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Tryptophan
Dermatitis - alopecia - enteritis
Each codon specifies only 1 amino acid

2. What is a silent mutation
Reads usual codon but inserts wrong AA
Consesus sequenec of base pairs
Assistance of upper extremities to stand up
Same AA - often base change in 3rd position of codon (tRNA wobble)

3. Where is PEP carboxykinase found - What does it do - and What does it require
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Hypoglycemia
Polyneuritis - symmetrical muscle wasting
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP

4. congenital microdeletion of long arm of chromosoe 7 with findings of elfin facies - mental retardation - hypercalcemia - well developed verbal skills - extreme friendliness with strangers - cardiovascular problems
Hypoxanthine to xanthing and xanthine to uric acid
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Williams syndrome

5. What is the activated carrier for 1 carbon units
THFs
Wernicke - korsakoff - dry and wet beriberi
MRNA - tRNA
Heterochromatin = HighlyCondensed

6. Do balanced translocations cause abnl phenotype
HVA
Supply sufficient glucose to brain and RBCs and to preserve protein
Degredation of TG circulating in chylomicrons and VLDLs
No

7. What is the RDE of cholesterol synthesis
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
HMG- CoA reductase
Antioxidant - protects RBCs and membrances from free radical damage

8. What is the defect in fructose intolerance and What does it cause
Inhibits 50S peptidyltransferase
Enhancers
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
FAP

9. What does a phosphorylase do
Autosomal recessive diseases
2 -4 DNP - aspirin
Carbomoyl phosphate synthetase I
Adds an inorganic phosphate onto substrate without using ATP

10. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
1 kind with multiple subunits
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Assistance of upper extremities to stand up
Adds an inorganic phosphate onto substrate without using ATP

11. What does the golgi apparatus do on asparagine
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Modifies N- oligosaccharides
Changed AA (convservative - new AA is similar in chemical structure)
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

12. How many nucTIDEs is a tRNA and What does the secondary sturcture form
75 to 90 - cloverleaf
GTP
Dermatitis - glossitis - and diarrhea
Promotor - TATA box - and CAAT box - AT rich

13. What is proteasomal degredation
Defect in fibrillin
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
Attachment of ubiquitin to defective proteins tag them for breakdown
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)

14. What does vit C def cause
Disorder of aromatic amino acid metabolism
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Tryptophan

15. 1 g of protein or cabrohydrate = ?kcal
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
Secretion of abnl thick mucus that plugs lungs - pancreas - liver
Debranching enzyme
Four

16. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Terminal regions - tropocollagen
P2 +2pq+ = 1
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
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

17. What is the RDE of de novo pyrimidine synthesis
DsRNA promotes degradation of target mRNA knocking down gene expression
Collagen
Carbomoyl phosphate synthetase II
Leu - lys

18. What ribosomes do prokaryotes have
30 - 50 - 70
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
PCR - denaturation - annealing - elongation
Mediates extra remnant take up

19. What are the results of pancreatic insuff in CF
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Vincritsine/vinblastine
Malabsorption and steatorrhea (ADEK)
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway

20. What two amino acids are required druing periods of growth and why
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Glycine
Arg and his inc in histones Which bind negatively charged DNA
ATPase that links peripheral 9 doublets and causes bending of cilium by differential sliding of doublets

21. What happens in a B12 def
TRNA
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
Neimann - pick - sphingomyelinase - sphingomyelin - AR
CAG - 4

22. inc glycogen in muscle but can't break it down - painful muscle cramps - myglobinuria with strenuous exercise - dz and enzyme

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

23. What is the physiologic role of dystrophin
Hypoxanthine to xanthing and xanthine to uric acid
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
Carnitine shuttle - acyl - coa from cyto to mito
Anchor muscle fibers - primarily in skeletal and cardiac muscle

24. Which antifungal drugs work on microtubules
NF2 on chromosome 22
Malabsorption and steatorrhea (ADEK)
Q -
Griseofulvin

25. What happens in zinc def
Phenylketones in urine
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Huntingtons

26. Why enzyme breaks down elastin and what enzyme inhibits it
Elastase - inhibited by alpha1 antitrypsin
Failure to track objects or develop a social smile
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

27. What are purines made from
IMP precursor
Wernicke - korsakoff - dry and wet beriberi
Mcardle's - skeletal muscle glycogen posphorylase
Consesus sequenec of base pairs

28. What does Adenosine deaminase deficiency cause a build up of - and What does that lead to?
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

29. What are the fat soluble vitamins and What does their absorption depend on...
IMP precursor
Von Gierke's - Pompe - Cori - McArdle
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Cri du chat

30. What are CDKs
Essential fructosuria - fructokinase AR
17 - 17 letters in von Recklinghausen
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Cyclin dependent kinases;constitutive and inactive

31. What is the Name and function of vit B2
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
Blood - bone marrown - amniotic fluid - placental tissue
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

32. Where is vit B12 found
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Proline and lysine - vit C
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Mutated dystrophin gene - less severe - adolescence

33. Mild Hurlurs + aggressive behavior no corneal clouding
APRT + PRPP
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent

34. Type I collagen
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Pseudomonas and s aureus
Cleft palate - cardiac abnl - pregs test

35. What is pleiotropy and given an example
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Targets the proteins for lysosome
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Q -

36. How does OTC def present
Infection - free radicals generated by inflammatory response
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
Bone - skin - tendon - dentin - fascia - cornea - late wound repair
Hypoxanthine to xanthing and xanthine to uric acid

37. How do cardia glycosides work
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
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
RNA poly II
Particular sequence of DNA where replicatino begins - may be single of multiple

38. What apolipoprotiens are on VLDL
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
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
Inhibits the Na/K pump by binding the K side
B-100 - CII and E

39. What are the purely ketogenic amino acids
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
O- oligosaccharaides
Leu - lys
Reads usual codon but inserts wrong AA

40. What is DNA cloning and How do you do it?
No - its non homologous
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
SnRNPs

41. benign asymptomatic condition with elevated levels of fructose in urine and blood - dz and enzyme
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
Essential fructosuria - fructokinase AR
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
Lysine and arginine

42. What is chediak higashi
Degradation of TG stored in adipocytes
SnRNPs and other proteins
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
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

43. What trinucleotide repeat in Huntingtons and what chromosome is it found on...
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
CAG - 4
1 ring
Conversion of NE to epi

44. Describe robertsonian translocation
Promotor - TATA box - and CAAT box - AT rich
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Superoxide dismutase

45. nucleotide repeat for fredreich's ataxia
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
GAA
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
OTC has hyperammonemia - orotic aciduira does not

46. What polar group does guanine have - and what non polar group does thymine have
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Changed AA (convservative - new AA is similar in chemical structure)
Ketone - methyl

47. What does the golgi assemble proteoglycans from
Core proteins
Fibroblast
Skin
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia

48. Type IV collagen is an important structural componenet of the BM for which 3 organs
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
Each codon specifies only 1 amino acid
Phenylethamolamine N methyl transferase
Kidney - ears - eyes

49. What are the symptoms of vit A def
MRNA
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Night blindness - dry skin
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

50. What rxn creates ATP
Failure to track objects or develop a social smile
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
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Fed