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 are cyclins
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Transmitted only through mother - all offspring of affected females may show signs of disease
APKD1 on chromosome 16
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan

2. What are the names and sources of the two types of vit D found in nature
Oxidized hemoglobin precipiated within RBCs
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Collagen

3. What is the RDE of glycogen synthesis
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Malabsorption and steatorrhea (ADEK)
CG- 3 > AT-2 - More CG content - melting point goes up
Glycogen synthase

4. What does vit B3 def result in
Cofactor for LPL
Abnormal protein folding - degradation before reaching cell surface
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
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

5. Which amino acids are elastin rich in
Proline and glycine (non glycosylated forms)
Lysine and leucine
Binds 50S - blocking translocation
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light

6. What kind of branches do glycogen branches have
Basement membrane or basal lamina
PMNs
Alpha 1 -6 and alpha 1 -4
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity

7. What is the structure of elastin
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Tropoelastin with fibrillin scafolding
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Inc melt - dec fluidity

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. Is there any requirement for homology in NHEJ
No - its non homologous
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Phosphofructokinase 1
Oxidized hemoglobin precipiated within RBCs

10. Type IV collagen
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Zero
Basement membrane or basal lamina
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer

11. How is vit D stored
Limit protein diet - benzoate or phenylbutarate (both bind amino acids leading to excretion) can decrease ammonia levels
Free ribosomes
9+2 arrangement of microtubules
25OHD3

12. What are the findings in PKU
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
G6PD
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor

13. What is the activated carrier for Co2
Purines= A - G pyrimidine = C - T (U)
Biotin
II - VII - IX - X (1972) protein C and S
Acetyl - CoA carboxylase (ACC)

14. What is the treatment for cystathionine synthase def
Kidney - ears - eyes
Dec methionine - inc cystiene - inc B12/folate
Acetyl - CoA
Hyperlipidemia

15. What are the complications/signs of familial hypercholesterolemia
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
Alpha - ketoglutarate dehydrogenase complex
Debranching enzyme
Mediates chylomicron secretion

16. How do microtubules grow and collapse
Defect in fibrillin
O- oligosaccharaides
Grows slowly - collapses quickly
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR

17. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
Terminal regions - tropocollagen
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
Adds 2 carbon with the help of biotin

18. What makes up a nucleoside
Mediates extra remnant take up
Base + ribose
Inc orotic acid in urine - megaloblastic anemia (does not correct with B12 or folate) - failure to thrive
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol

19. How does chloramphenicol work
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Glycogenolysis to form glucose
Inhibits 50S peptidyltransferase
IMP precursor

20. What is the function of folic acid
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Achondroplasia
Transmitted only through mother - all offspring of affected females may show signs of disease

21. What polar group does guanine have - and what non polar group does thymine have
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
APRT + PRPP
Ketone - methyl
MRNA - tRNA

22. Formed and degradation of VLDL - delivers TGs and cholesterol to liver where they are degraded to LDL
Reads usual codon but inserts wrong AA
GTP
IDL
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene

23. What happens with wet beriberi
VLDL
Remain in G0 - regenerate from stem cells - neurons - skeletal/cardiac muscle - RBCs
TRNA
High output cardiac failure - dilated cardiomyopathy - edema

24. What does the addition of mannose -6 phosphate do
GAA
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Targets the proteins for lysosome
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue

25. What do B- complex vitamin deficiencies often result in
Inc insulin - dec cAMP - dec PKA
Dermatitis - glossitis - and diarrhea
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet

26. What ribosomes do eukaryotes have
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact
40 - 60 - 80
Lysine and leucine
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

27. What is the TX for pyruvate dehydrogenase deficiency
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
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
Purines= A - G pyrimidine = C - T (U)

28. What is regeneration of methionine depedent on...
Polyneuritis - symmetrical muscle wasting
B12 and folate
Two
Mental retardation - seizures - ataxia - inappropriate laughter - deletion of normally active maternal allele

29. What happens in carnitine def
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Muscle

30. What part of the pre mRNA contains the actual genetic information coding for protein
Exons
Carnitine acyltransferase I
Silencers
Lactate

31. What are the results of pancreatic insuff in CF
Flagella - cilia - mitotic spindles
Acetyl - CoA carboxylase (ACC)
Malabsorption and steatorrhea (ADEK)
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration

32. Type III collagen
Males are infertile due to bilateral absence of vas deferens
Inhibits RNA polymerase II - found in death cap mushrooms
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
4 under the floor

33. What is the most abundant protein in the body
Collagen
Glycogen and FFA oxidation; glucose conserved for final sprinting
No
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response

34. What other inflammatory process can induce a hemolytic anemia in NADPH defieicnt patients
Infection - free radicals generated by inflammatory response
HGPRT - defective purine salvage - excess uric acid production
Diphyllobothrium latum
Catabolic processes to carry reducing equivalents away as NADH

35. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Silencers
Oxidative and nonoxidative - no ATP produced or used
FAP
Proton gradient

36. What bone disorder has x linked dominant inheritance
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
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)
Krabbes - galactocerebrosidase - galactocerebroside - AR
Conversion of NE to epi

37. What is the order of severity for the different types of mutations
Adenosine to inosine
Cri du chat
Retardation - self mutilation - aggression - hyperuricemia - gout - choreoathetosis
Nonsense > missense > silent

38. What is the target of the 3' hydroxyl attack
Fed
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
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
The triphosphate bond

39. What enzyme adds Cl - to the H202 to makes bleach
Glucose - 2Pi - 2ADP - 2NAD+
Myeloperoxidase
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Phosphofructokinase 1

40. Leysh - Nyhan syndrome is a defect in which enzyme and What are the biochemical results
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
HGPRT - defective purine salvage - excess uric acid production
B48 - AIV - CII - E
Mediates chylomicron secretion

41. What inhibits pyruvate kinase
Glycogen and FFA oxidation; glucose conserved for final sprinting
ATP and alanine
Hereditary spherocytosis
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

42. What is the result of vit B5 def
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
NF2 on chromosome 22
Promotor - TATA box - and CAAT box - AT rich
Alanine

43. What are the findings in Down's syndrome
Leu - lys
N to C
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
RER

44. What is the trinucleotide repeat in fragile X
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
PFK - rate limiting enzyme
CGG

45. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Lysine and arginine
Marasmus - muscle wasting
Read from a fixed starting point as a continuous sequence of bases
Disorder of aromatic amino acid metabolism

46. central and peripheral demyelination with ataxia and dementia
Avidin
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR
Covalent cross - linking by lysyl oxidase to make collagen fibrils

47. What is the amino acid precursor for GABA and glutathione
Schwann cells - lens - retina - kidneys
Glutamate
Kidney - ears - eyes
Glycogen synthase

48. elevated LDL due to defective or absent LDL receptor - heterozygotes have cholesterol ~300 - homozygotes ~700
ATP hyrdolysis couple to energetically unfavorable rxns
Familial hypercholesterolemia - hyperlipidemia type IIA
UGA - UAA and UAG
Sucrose = glucose + fructose - lactose = glucose + galactose

49. What does arsenic do and What are th results of poisoning
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Fructose 1 -6 bisphosphate
Grows slowly - collapses quickly
Failure to track objects or develop a social smile

50. What two enzymes are involved in EtOH metabolism
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
Active secretion in lungs and GI - reabsorbs in skin
EtOH dehydrogenase and acetaldehyde dehydrogenase