ALL 2 Flashcards
Select the INCORRECT pair relating to the specificity of ligands and receptors:
Adrenaline and muscarinic acetylcholine receptor
Incorrect because adrenaline binds to adrenergic receptors, not muscarinic acetylcholine receptors.
Glucagon and the GlucaGen HypoKit:
Glucagon uses a G protein-coupled receptor to produce signal transduction.
Correct: Glucagon receptors are GPCRs.
Second messenger NOT used by GPCRs:
Adenylate cyclase
Adenylate cyclase is an enzyme, not a second messenger.
INCORRECT statement regarding receptor proteins:
Receptors release the ligand as a changed product.
Incorrect: Receptors typically do not chemically change ligands.
Good chemical starting point for discovering a GPCR antagonist:
The endogenous ligand for their target receptor.
This would be a good starting point for discovering an antagonist.
Flow of genetic information in a cell:
DNA -> mRNA -> Protein.
Translation is the synthesis of:
Protein from an mRNA template.
Key elements of a gene:
Promoter region, exons, transcription factor binding sites, introns.
Alternate forms of a gene are called:
Alleles.
True statement about the inheritance of alleles:
One allele comes from each parent.
Parents’ genotypes if two straight-haired people have a curly-haired child:
Heterozygous.
Least likely genetic variant to have severe consequences:
A variant that changes a codon to another codon for the same amino acid.
How a person’s genotype can be determined:
All of the above.
All listed assays can be used for genotyping.
Who will show symptoms of the genetic disease (from gel image):
Person 2.
Person 2 has the homozygous recessive genotype.
Why PCR is commonly used in genetic testing:
It generates a large number of copies of a specific DNA region.
Sickle Cell Anaemia is:
A monogenic disease caused by the E6V haemoglobin genetic variant.
A disease or disorder can be:
All of the above.
Diseases can have varying degrees of genetic and environmental causes.
Genetic variant that could cause a severe phenotype:
Anywhere in a reaction pathway.
The effect of a genetic variant on a phenotype can be modified by the environment if:
The genetic variant does not severely change the protein’s function.
Best explanation for why older people have a higher chance of getting cancer:
Because their DNA has been damaged over time.
A complex disease is:
Caused by multiple, complicated gene-environment interactions.
Best host to produce functional “PepZ” (requiring gamma-carboxylation):
Chinese Hamster Ovary Cells.
NOT an advantage of using eukaryotic cells for therapeutic protein production:
Can make proteins from any tissue.
Eukaryotic cells cannot make all proteins.
INCORRECT statement about recombinant expression vectors:
They are double-stranded pieces of linear DNA.
They are circular DNA.
Protein type and recombinant production systems NOT correctly paired:
Glycosylated protein and bacteria.
Bacteria do not glycosylate proteins.
Restriction enzymes cut:
DNA at specific sites.
Correct statement about human insulin:
The A and B chains of human insulin can be synthesized recombinantly without the requirement for in vivo post-translational modifications.
Recombinant insulin is produced in:
E.coli.
Erythropoietin (EPO):
Can be used to treat anaemic cancer patients.
Genes containing introns cannot be expressed in bacteria because:
Bacteria do not have the cellular machinery required for splicing out introns.
Statement about EPO and insulin production in E. coli:
EPO produced in E. coli is not functional because it requires glycosylation.
C. Can be used to treat anaemic cancer patients.
D. Bacteria do not have the cellular machinery required for splicing out introns.
Example sentence: Bacteria lack the necessary enzymes for intron splicing.
Statement about EPO and insulin production in E. coli:
A. EPO produced in E. coli is not functional because it requires glycosylation.
Example sentence: EPO needs glycosylation for proper function.
Restricting expression of recombinant proteins to specific tissues in animals can be controlled by:
B. A mammalian cell-type specific promoter.
Example sentence: Specific promoters can target expression to certain tissues.
Major benefit of gene therapy:
B. It can treat genetic disorders at their source.
Example sentence: Gene therapy addresses the root cause of genetic disorders.
Statement about dilution of solution A (12 mL of solution A mixed with 24 mL of solution B):
C. The undiluted solution A had a concentration of 90 mg/mL.
Example sentence: The original concentration of solution A was 90 mg/mL.
Volume delivered by the pipette:
C. 350 μL.
Example sentence: The pipette dispensed 350 microliters of liquid.
50 mmol/μL equals:
A. 0.05 mol/mL.
Example sentence: 50 millimoles per microliter is equivalent to 0.05 moles per milliliter.
A 1 in 12 dilution of an enzyme means:
A. 1 part enzyme diluted with 11 parts of buffer.
Example sentence: A 1 in 12 dilution involves adding 1 part enzyme to 11 parts buffer.
To dilute a solution from 90 mg/mL to 15 mg/mL:
B. 1 part solution to 6 parts water.
Example sentence: Diluting from 90 mg/mL to 15 mg/mL requires mixing 1 part solution with 6 parts water.
Structural component of starch responsible for blue-black colour in iodine test:
A. Amylose.
Example sentence: Amylose is the starch component that gives a blue-black color with iodine.
High heat (80°C) affects bonds stabilising protein:
B. Secondary, tertiary, and quaternary structure.
Example sentence: Protein structure is affected at 80°C, impacting secondary, tertiary, and quaternary bonds.
Beer’s Law in spectrophotometry indicates:
C. Concentration of the solution.
Example sentence: Beer’s Law relates absorbance to solution concentration.
Lambert’s Law in spectrophotometry indicates:
C. Decreases logarithmically with increasing pathlength.
Example sentence: Lambert’s Law describes the logarithmic decrease in absorbance with longer pathlengths.
In the Beer-Lambert Law, the term ‘l’ denotes:
C. Light-path length.
Example sentence: The variable ‘l’ in the Beer-Lambert Law represents the distance light travels through the sample.
Wavelength at which a molecule absorbs light maximally:
D. Can be determined by constructing an absorbance spectrum.
Example sentence: Absorbance spectra help identify the wavelength of maximum light absorption for a molecule.
INCORRECT statement about spectrophotometry:
C. The wavelength of a standard cuvette is 1 cm.
Example sentence: The path length, not the wavelength, of a standard cuvette in spectrophotometry is typically 1 cm.
Correct statement about enzyme assays and absorbance:
A. When using enzyme assays to analyse complex solutions for specific molecules, it is assumed that the reaction goes to completion.
Example sentence: Enzyme assays assume complete reaction to analyze complex mixtures for specific molecules.
Dilution of solution A (80 mL of solution A added to 720 mL of water):
B. 1 in 10 dilution.
Example sentence: Diluting solution A by adding 720 mL of water to 80 mL results in a 1 in 10 dilution.
Reason for the decrease in gradient of a progress curve:
B. Substrate concentration decreases over the reaction period.
Example sentence: The decline in gradient on a progress curve is due to decreasing substrate concentration during the reaction.
Good standard curve (absorbance plotted against concentration):
B. I and III (passes through the origin and is a straight line).
Example sentence: A standard curve that intersects the origin and is linear is considered good for absorbance versus concentration.
Alcohol dehydrogenase catalyses the conversion of:
A. Ethanol to acetaldehyde.
Example sentence: Alcohol dehydrogenase converts ethanol into acetaldehyde.
INCORRECT statement about C-blue solution absorbance:
A. The concentration of the 1 in 6 diluted C-blue sample is 15 mmol/L.
Example sentence: The correct concentration for the 1 in 6 diluted C-blue sample is not 15 mmol/L.
Correct concentration of diluted solution Y based on absorbance:
C. 11.4 μmol/L.
Example sentence: The concentration of diluted solution Y, determined by absorbance, is 11.4 micromoles per liter.
Initial velocity of assay using 200 μL of ADH:
A. 0.075 ΔA/s.
Example sentence: The initial velocity of the assay with 200 μL of ADH is 0.075 absorbance units per second.
KM for enzyme from Lineweaver-Burk graph:
C. 2.5 mmol/L.
Example sentence: The KM value for the enzyme, obtained from the Lineweaver-Burk plot, is 2.5 millimoles per liter.
Vmax for enzyme from Lineweaver-Burk graph:
B. 0.2 ΔA/min.
Example sentence: The Vmax value for the enzyme, derived from the Lineweaver-Burk graph, is 0.2 absorbance units per minute.
