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 tissue samples are used for karyotyping
Dermatitis - alopecia - enteritis
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
CAG - 4
Blood - bone marrown - amniotic fluid - placental tissue

2. What are the results of unbalanced translocation
Site of steroid synthesis and detoxification of drugs and poisons
Miscarriage - stillbirth - chromosomal imbalance (down - patau)
Lariat shape in order and remove intron precisely and join 2 exons
Mcardle's - skeletal muscle glycogen posphorylase

3. Mediates reverse cholesterol transport from periphery to liver - acts as respository for apoC an apoE - secreted from both liver and small intestine
Liver hepatocytes and steroid producing cells of the adrenal cortex
Base + ribose + phosphate (3' -5') phosphodiester bond
HDL
Alanine

4. How do aminoglycosides work
Mitochondria
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
By inhibiting formation of the initiation complex and cause misreading of mRNA
Assistance of upper extremities to stand up

5. What happens at the smooth ER
AMP - fructose 2 -6 BP
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Site of steroid synthesis and detoxification of drugs and poisons
Dermatitis - enteritis - alopecia - adrenal insuff

6. in a 100 meter sprint Where does energy come from
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
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
Stored ATP - creatine phosphate - anaerobic glycolysis
Huntingtons

7. Which direction does kinesin go
Degredation of TG circulating in chylomicrons and VLDLs
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Initiate chains
Neg to pos

8. hepatosplenomegaly - aseptic necrosis of femur - bone crisis - MACS that look like crumpled tissue paper

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

9. Type IV collagen
ATP
Basement membrane or basal lamina
Glutamate
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females

10. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
Facial flushing
Von hippel lindau - 3
Oral uridine administration
Acetyl - CoA

11. What does apoB100 do
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Disease
Binds to LDL receptor - mediates VLDL secretion
Mediates extra remnant take up

12. Where are cytosolic and organellar proteins made
SNP
Facial flushing
Kidney - ears - eyes
Free ribosomes

13. Where is vit A found in the diet
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
Epithelial cells
Liver and leafy veggies
O- oligosaccharaides

14. How do tetracyclines work
Bind 30s subunit preventing attachment of aminoacyl - tRNA
Rb and p53
Failure to track objects or develop a social smile
2 -4 DNP - aspirin

15. What are the characteristics of angelmans syndrome and How does it occur
Lactate
Basement membrane or basal lamina
Paclitaxel
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

16. What substance in egg whites binds biotin
2 rings
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Avidin
Free ribosomes

17. Why is albinism inheritnace varialbe due to...
P+q = 1
Locus heterogeneity - ocular albinism is x- linked recessive
Same as sprint + OXPHOS
Breaks down acyl - coa to acetyl coa groups in mito

18. What is anticipation and give an example
Breaks down acyl - coa to acetyl coa groups in mito
Oligomycin
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
LCAT (lecithin cholesterol acyltransferase)

19. What causes Down syndrome
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Alpha 1 -6 and alpha 1 -4
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
2 -4 DNP - aspirin

20. What do def in in enzymes of gluconeogenesis cause
Hypoglycemia
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Wrinkles and acne
OTC has hyperammonemia - orotic aciduira does not

21. What is heteroplasmy
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Pyruvate to oxaloacetate (3C to 4C)

22. cardiomegaly - systemic findings leading to early death - 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 defectin IV - hypertriglyceridemia
B100
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

24. Name 5 drugs that interfere with nucleotide synthesis
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
APRT + PRPP
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Supply sufficient glucose to brain and RBCs and to preserve protein

25. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
Liver - also in kidney and gut epithelium
Degredation of TG circulating in chylomicrons and VLDLs
CAG - 4
32 - malate aspartate shuttle

26. What can vit B3 be used to treat
Hyperlipidemia
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Proton gradient
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

27. 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)
Protein
Oxidative and nonoxidative - no ATP produced or used
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive

28. What is the hardy weinberg allele prevalence
P+q = 1
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Breaks down acyl - coa to acetyl coa groups in mito
Mcardle's - skeletal muscle glycogen posphorylase

29. What are the findings in Lesch - Nyhan
3' end (with CCA)
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Semiconservative - continuous and discontinuous strands (okazaki fragments)
Oxidized hemoglobin precipiated within RBCs

30. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Protein kinase A
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Histidine
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA

31. What polar group does guanine have - and what non polar group does thymine have
Ketone - methyl
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Methionine encode by only 1 codon (AUG)

32. What regulates whether FBPase -2 or PFK-2 is active
Myeloperoxidase
Protein kinase A
ATP hyrdolysis couple to energetically unfavorable rxns
Orotic acid to UMP

33. Inhibition of thymidilate synthase and and DHFR lead to decrease In what substance
Assistance of upper extremities to stand up
THFs
Foliage - small reserve in liver - eat green leaves
DTMP

34. What substances are uncouling agents
Pyruvate to oxaloacetate (3C to 4C)
2 -4 DNP - aspirin
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
NF2 on chromosome 22

35. What does a phosphorylase do
32 - malate aspartate shuttle
Adds an inorganic phosphate onto substrate without using ATP
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis

36. What converts limit dextran to glucose
Terminal regions - tropocollagen
Medial dorsal nucleus of thalamus - mamillary bodies
Debranching enzyme
Oxalacetate

37. What substance inside the cell reduces glutatione
DNA
NADPH
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Williams syndrome

38. What is the breakdown product of dopamine
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
HVA
Phenylketones in urine
Dopamine beta hydroxylase

39. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
Hereditary spherocytosis
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
Familial hypercholesterolemia - hyperlipidemia type IIA
2 -4 DNP - aspirin

40. What is the smallest mutation a mircoarray can detect
Purines= A - G pyrimidine = C - T (U)
Orotate precursor - with PRPP added later
Neuralgia
SNP

41. Which type of chromatin is less condensed - transcriptionally active - sterically accesible
Basement membrane or basal lamina
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
HMG- CoA reductase
Euchromatin

42. What are the two possible causes of albinism
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
L form
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)
1 kind with multiple subunits

43. decreases In what substances can cause PKU
Phenylalanine hydroxylase - tetrahydrobiopterin cofactor
Hypoxanthine to xanthing and xanthine to uric acid
APKD1 on chromosome 16
Avidin

44. What kind of RNA is transported out of the nucleus
HMG- CoA reductase
Free ribosomes
30 - 50 - 70
Only processed RNA

45. What are the glucogenic essential amino acids
Consesus sequenec of base pairs
Met - val - arg his
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Disorder of aromatic amino acid metabolism

46. What is the Name and fxn of vit B5
Neurofibromatosis type 1 (von Recklinghausens disease)
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.

47. What is trimming
Removal of N or C termal propeptides from zymogens to generate mature proteins
CG- 3 > AT-2 - More CG content - melting point goes up
Alpha 1 -6 and alpha 1 -4
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

48. Wgat substances directly inhibit mitochondrial ATPase - causing an inc in proton gradient - no ATP because pump is stopped
Mediates chylomicron secretion
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
VLDL
Oligomycin

49. What tissues have only aldose reductase
Schwann cells - lens - retina - kidneys
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Glycogen phosphorylase
Lysine and leucine

50. How many ATP are created by aerobic metobolism of glucose in muslce via what shuttle
Particular sequence of DNA where replicatino begins - may be single of multiple
30 - glycerol -3- phosphate shuttle
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Blood - bone marrown - amniotic fluid - placental tissue