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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 are the 3 AR forms of homocystinuria
UDP glucose pyrophosphorylase
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
EtOH dehydrogenase and acetaldehyde dehydrogenase
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation

2. What is the RDE of ketogenesis
CGG
HMG- CoA synthase
Phosphorylation excess glucose to sequester it - liver becomes blood glucose buffer
Alpha1 antitrypsin

3. What is the Name and fxn of vit B5
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
NF2 on chromosome 22
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Activates LCAT

4. What is the energy source for tRNA actication (charging)
ATP
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
VLDL
Glucose 6 phosphate dehydrogenase (G6PD)

5. What does a phosphatase do
Marfans
Removes phosphate group from substrate
Hypoglycemia
Semiconservative - continuous and discontinuous strands (okazaki fragments)

6. Which tumor suppresors inhibit G1 to S progression - where mutations result in unrestrained growth
Rb and p53
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
Ribos first then deoxyribos with ribonucleotide reductase
Ketone - methyl

7. What is the origin of replication
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
Particular sequence of DNA where replicatino begins - may be single of multiple
HMP shunt
CGG

8. What is the amino acid precursor for GABA and glutathione
Glutamate
Assistance of upper extremities to stand up
Proline and lysine - vit C
Inhibits lipoic acid - vomiting - rice water stools - garlic breath

9. What does apoE do
Comlex II
Neonatal hemorrhage with inc PT and PTT - but nl bleeding time - can also occur after prolonged use of broad spectrum Abx
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Mediates extra remnant take up

10. Which aspect of the spliceosome do patients with lupus make antibodies against
SnRNPs
Tryptophan excretion in urine and dec absorption from the gut leading to pellagra
Degradation of TG remaining in IDL
HVA

11. Of the four possible fates for pyruvate - which one can replenish TCA cycle or be used in gluconeogenesis
Oxalacetate
Alpha - ketoglutarate dehydrogenase complex
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Rb and p53

12. What makes up a nucleotide

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13. Of the four possible fates for pyruvate - which one is a transition from glycolysis to TCA cycle
Niacin - constituent of NAD and NADP - derived from tryptophan
1 kind with multiple subunits
Acetyl - CoA
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

14. What does the ELISA test for
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
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Neural tube
Antigen - antibody reactivity - can look for antigen or antibody in patients blood

15. What is the defect in I- hyperchylomicronemia
Antibiotic use or excessive ingestion of raw eggs
Q -
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

16. What is the RDE of cholesterol synthesis
HMG- CoA reductase
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
OTC has hyperammonemia - orotic aciduira does not
Euchromatin

17. What rxn creates ATP
Change resulting in early stop codon
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Collagen
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

18. Type IV collagen is an important structural componenet of the BM for which 3 organs
Kidney - ears - eyes
Rotenone - CN- - antimycin A - CO
Antibiotic use or excessive ingestion of raw eggs
Abnormal protein folding - degradation before reaching cell surface

19. What lab value can distinguish orotic aciduria from ornithine transcarbamoylase def?
OTC has hyperammonemia - orotic aciduira does not
Inhibits the Na/K pump by binding the K side
Metanephrine
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

20. characterize autosomal domint inheritance
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Many generations - both male and female affected - often pleiotropic - can present clinically after puberty
Two

21. What reaction does adenosine deaminase normally catalyze
Lactate
B48 - AIV - CII - E
Cofactor for LPL
Adenosine to inosine

22. Describe the structure of cilia
9+2 arrangement of microtubules
RRNA
Mitochondria
Alcohol version of glucose - can trap glucose in cell - aldose reductase

23. progressive neurodegeneration - developmental delay - cherry red spot on macula - lysosomes with onion skin - NO hepatosplenomegaly
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
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Tay- Sachs - hexosaminidase A - GM2 ganglioside - AR
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

24. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Post to neg
4 under the floor
Hereditary spherocytosis
Euchromatin

25. energy malnutrition resulting in tissues and muscle wasting - loss of subQ fat - variable edema
Marasmus - muscle wasting
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
30 - 50 - 70
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

26. What is NAD+ generally used for
Mediates chylomicron secretion
Alpha and beta tubulin - dimers have two GTP bound
PCR - denaturation - annealing - elongation
Catabolic processes to carry reducing equivalents away as NADH

27. Broadly - What can cause fat - soluble vitamin deficiencies
OTC has hyperammonemia - orotic aciduira does not
Malapsorption syndromes like sprue or CF or mineral oil intake
Thymic - parathyroid and cardiac
1 -25 OH2 D3 = calcitriol

28. Of the four possible fates for pyruvate - which ends anaerobic glycolysis as in RBCs - leukocytes - kidney medulla - lens - testes and cornea
2 rings
Huntingtons
Lactate
Cori's - debranching enzyme alpha 1 -6 glucosidase - gluconeogenesis intact

29. CF - is AR deletion In what gene On what chromosome resulting in a deletion inf what?
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
UDP glucose pyrophosphorylase
Ribos first then deoxyribos with ribonucleotide reductase
CFTR gene - 7 - Phe 508

30. Name 5 drugs that interfere with nucleotide synthesis
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
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
Superoxide dismutase
Arg - lys - his - arg is most basic - has has no charge at body pH

31. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
Ribos first then deoxyribos with ribonucleotide reductase
HMG- CoA reductase
Glucose - 2Pi - 2ADP - 2NAD+
Malonyl coa

32. What are the priorities for the body in fasting and starvation
Supply sufficient glucose to brain and RBCs and to preserve protein
Mediates chylomicron secretion
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
F16BP

33. How do you diagnose CFTR
Wernicke - korsakoff - dry and wet beriberi
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
SNP
Inc Cl - in sweat

34. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Phosphofructokinase 1
AR
Fed
Karyotyping

35. Which direction does kinesin go
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
Disease
Neg to pos
Lariat shape in order and remove intron precisely and join 2 exons

36. What does the golgi do to sugars in proteoglycans and of selected tyrosine on proteins
Sulfation
Enter G1 from G0 when stimulated - hepatocytes and lymphocytes
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Alpha 1 -6 and alpha 1 -4

37. Where are the secretory proteins made and N- linked oligosaccharide addtions put on proteins
Glycogen synthase
Thymic - parathyroid and cardiac
RER
Alpha and beta tubulin - dimers have two GTP bound

38. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Asp and Glu
Chronic granulomatous disease - no respiatory burst - no formatino of ROS
Sucrose = glucose + fructose - lactose = glucose + galactose
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver

39. Describe robertsonian translocation
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
PCR - denaturation - annealing - elongation
Exons
Phosphorylation - glycosylation - hydroxylation

40. What is the prevalence of an X- linked recessive disease in males and in females
Phosphofructokinase 1
Q -
Scrutinizes - hydrolyzes the bond
Robertsonian translocation and mosaicism

41. What is the most abundant protein in the body
Collagen
Debranching enzyme
ATP - citrate
Type II

42. What is the complication of cystinuria
Anabolic processes as a supply of reducing equivalents
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
African Americans and Asians
Result from phagocytic removal of heinz bodies my macs - G6PD def

43. What does the addition of mannose -6 phosphate do
4 under the floor
No mutation occuring at the locus - no selection for any genotypes at the locus - completely random mating - no migration
Four
Targets the proteins for lysosome

44. What is pleiotropy and given an example
X linked frame shif mutation
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP

45. The pyruvate dehydorgenase complex serves In what reaction: reactants
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Changed AA (convservative - new AA is similar in chemical structure)
Pyruvate - NAD+ - CoA

46. What does Alports syndrome cause and why
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
IDL
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two

47. In what cells do the respiratory burst occur
Alcohol version of glucose - can trap glucose in cell - aldose reductase
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Exons
PMNs

48. What are CDKs
5' to 3'
Keep glutathione reduced so it can detoxify free radicals and peroxides
Cyclin dependent kinases;constitutive and inactive
Degradation of TG stored in adipocytes

49. Where does gluconeogenesis primarily happen and What are other sites where the enzymes are located
Alkaptonuria - may have debiliating arthralgias
Liver - also in kidney and gut epithelium
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
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

50. Which are the acidic amino acids
Asp and Glu
Neurons
Essential fructosuria - fructokinase AR
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