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 does apoE do
Blood - bone marrown - amniotic fluid - placental tissue
THFs
Mediates extra remnant take up
Wobble

2. What two amino acids are required druing periods of growth and why
Arg and his inc in histones Which bind negatively charged DNA
Malonyl coa
Cre - lox system
Result from phagocytic removal of heinz bodies my macs - G6PD def

3. What does Citrate Is Krebs starting substrate for making oxaloacetate
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
HMG- CoA reductase
Exons
By inhibiting formation of the initiation complex and cause misreading of mRNA

4. What are cyclins
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Acetly- CoA - CO2 - NADH
Glutamine PRPP amidotransferase
Grows slowly - collapses quickly

5. What is the energy source for tRNA actication (charging)
Glycogen and FFA oxidation; glucose conserved for final sprinting
Hypoxanthine to xanthing and xanthine to uric acid
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
ATP

6. What are the priorities for the body in fasting and starvation
Assistance of upper extremities to stand up
Alpha1 antitrypsin
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Supply sufficient glucose to brain and RBCs and to preserve protein

7. What are uncoupling agents
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
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
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

8. What defects characterize velocardiofacial syndrome
Palate - facial and cardiac defects
G6PD
HGPRT - defective purine salvage - excess uric acid production
Coenzyme A - lipoamide

9. What does DNA poly III do?

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

10. What does degenerate/rundant genetic code refer to...
Alpha and beta tubulin - dimers have two GTP bound
RRNA
Hyperlipidemia
More than 1 codon may code for the same amino acid

11. What is the TX for pyruvate dehydrogenase deficiency
Connective tissue
Griseofulvin
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine

12. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Comlex II
Sucrose = glucose + fructose - lactose = glucose + galactose

13. What are the characteristics of angelmans syndrome and How does it occur
Fasting
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele
Neurons
Carbomoyl phosphate synthetase II

14. Accurate base pairing is required only in the first two nucleotide positions of an mRNA codon - so conds differeing in the 3rd position may code for the same tRNA/AA due to degenerate genetic code
Dopa decarboxylase
Lysine and leucine
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Wobble

15. nucleotide repeat for fredreich's ataxia
CGG
Heterochromatin = HighlyCondensed
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
GAA

16. What are the 3 AR forms of homocystinuria
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Neg to pos
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)
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def

17. delivers hepatic TGs to peripheral tissue - secreted by liver
Glycogen phosphorylase
Myeloperoxidase
VLDL
Niacin - constituent of NAD and NADP - derived from tryptophan

18. What test is used for B12 def
Schilling test
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
Debranching enzyme
Oxalacetate

19. What two cells are particularly rich in RER
Elastase - inhibited by alpha1 antitrypsin
Mucus secreting globlet cells and antibody secreting plasma cells
II - VII - IX - X (1972) protein C and S
Dermatitis - alopecia - enteritis

20. What does a decrease in decrease in NADPH lead to and why
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Epithelial cells
DsRNA promotes degradation of target mRNA knocking down gene expression

21. What does fomepizole do
Alcohol version of glucose - can trap glucose in cell - aldose reductase
2pq
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx

22. What enzymes metabolize fatty acids and amino acids
5' of the incoming nucleotide
Von gierkes - glucose 6 phosphatase
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
Acetoacetate and beta hydroxybutyrate

23. What does a phosphatase do
Facial flushing
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Base + ribose
Removes phosphate group from substrate

24. What is the activated carrier for electrons
BOne
Carnitine shuttle - acyl - coa from cyto to mito
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
NADH - NADPH - FADH2

25. What bone disorder has x linked dominant inheritance
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
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
Antioxidant - protects RBCs and membrances from free radical damage
Glycogen phosphorylase

26. In eukaryotes - What does RNA poly III make
Flagella - cilia - mitotic spindles
TRNA
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Epithelial cells

27. What stretch of DNA that alters gene expression by binding of transcription factors
HMG- CoA reductase
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Cofactor for LPL
Enhancers

28. What are the water soluble vitamins - which ones are stored
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
Mitochondria
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
1 -25 OH2 D3 = calcitriol

29. What is the fxn of vit D
Phosphofructokinase 1
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
VMA

30. What are pyrimidines made from
CGG
4 under the floor
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Orotate precursor - with PRPP added later

31. What does a pyruvate dehydrogenase deficiency lead to and What are the findings
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Marasmus - muscle wasting
Niacin - constituent of NAD and NADP - derived from tryptophan
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects

32. 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
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Kidney - ears - eyes
Williams syndrome
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

33. characterize mitochondrial inheritance
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Free ribosomes
IMP precursor
Transmitted only through mother - all offspring of affected females may show signs of disease

34. What do def in in enzymes of gluconeogenesis cause
Inhibits the Na/K pump by binding the K side
40 - 60 - 80
Hypoglycemia
Vincritsine/vinblastine

35. Delivers hepatic cholesterol to peripheral tissues - formed by LPL modification of VLDL in the peripheral tissue - taken up by target cells via RME
LDL
Alpha - ketoglutarate dehydrogenase complex
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
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

36. What is the result of vit B5 def
9+2 arrangement of microtubules
Phosphorylation - glycosylation - hydroxylation
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Type II

37. Which direction does dynein go
Disorder of aromatic amino acid metabolism
Post to neg
Neither of 2 alleles is dominant - blood groups
Glycine - aspartate - glutamine

38. FAP is due to deletion On what gene On what chromosome
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Dermatitis - enteritis - alopecia - adrenal insuff
APRT + PRPP
APC on chromosome 5

39. fibrillin defect leading to connective tissue disorder affecting skeleton - heart - and eyes
IDL
RRNA
Marfans
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -

40. Which type of chromatin is condensed - transcriptionally inactive - sterically inaccessible?
ATP - citrate
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Heterochromatin = HighlyCondensed
32 - malate aspartate shuttle

41. What is a silent mutation
Oxalacetate
Same AA - often base change in 3rd position of codon (tRNA wobble)
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA

42. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
APKD1 on chromosome 16
Wobble

43. Type II collagen
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Alpha 1 -4 glucosidase
Cartilage - hyaline - vitreous body - nucleus pulposus
Semiconservative - continuous and discontinuous strands (okazaki fragments)

44. What do neurofilaments stain for
LCAT (lecithin cholesterol acyltransferase)
TRNA
Neurons
Citrate - acetyl coa from mito to cyto

45. What is the RDE of de novo purine synthesis
Glutamine PRPP amidotransferase
Conversion of NE to epi
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Glucose - 2Pi - 2ADP - 2NAD+

46. cytoskeletal elements associated with cilia - flagella - mitotic spindle - neurones and centrioles
Microtubules
Neither of 2 alleles is dominant - blood groups
Exercise: inc NAD/NADH - inc ADP - inc Ca
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive

47. What is the exception to genetic redundancy
Inc CPK and muscle biopsy
Orotate precursor - with PRPP added later
AMP - fructose 2 -6 BP
Methionine encode by only 1 codon (AUG)

48. What do the single stranded binding proteins do
Prevent strands from reannealing
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss

49. Where is vit B12 found
Fructose via sorbitol dehydrogenase - inc sorbitol leading to osmotic damage as in cataracts - retinopathy - peripheral neuropathy as in diabetes
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Glycogenolysis to form glucose
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

50. What is the energy source for translocation
Glycogen phosphorylase
Facial flushing
GTP
Avidin