FREE ASCP Technologist in Molecular Biology Questions and Answers
Which of the following best describes a mutation involving base substitution? AGTCGA is the initial DNA sequence.
Because only a single nucleotide is changed without affecting the total number of bases, AGTAGA is the sole option that can be considered a base substitution mutation.
Which kind of domination is exemplified by the blood type of humans?
The response of codominance is accurate. Although there are just three blood type alleles, there are four different human blood types (A, B, AB, and O). For human blood type, both alleles are present, allowing for the potential of an AB blood type, as opposed to total dominance of one allele over the other or a mixing of alleles.
Which technique can assist in identifying a poisonous drug present in a person's bloodstream?
By generating ions of the compounds present in the sample and then applying forces to the ions to measure their deflection, mass spectrometry aids in the identification of unknown substances. The mass spectrum produced by the differential deflection of ions is specific to the molecule and helps identify it.
A collection of cells absorbs DNA that is floating freely in their surroundings. Here's an illustration of:
This is an illustration of a form of horizontal gene transfer known as transformation. Though they are also forms of horizontal gene transfer, transduction and conjugation do not entail the uptake of freely floating DNA.
Which of the following would best identify the presence of metabolites in bodily fluids? Mitochondrial abnormalities can be identified by the presence of metabolites in the bloodstream, urine, or cerebral spinal fluid.
The only method that can identify the presence of metabolites is mass spectrometry. The two other techniques, PCR and in-situ hybridization, identify the presence of nucleic acids, while western blot is used to identify the presence of proteins.
Which two polymerizing agents are typically utilized in the casting process of polyacryamide gels?
Two polymerizing agents that are frequently employed in the casting of acylamide gels are TEMED and APS. Nucleic acid acids are extracted from polyacrylamide gels with the aid of sodium chloride, and DMSO is a common solvent.
What kind of horizontal gene transfer is the foundation for the process known as electroporation, which enables cells to absorb large molecules like DNA?
Any DNA transfer that does not originate from sexual or asexual reproduction is known as horizontal gene transfer. Electrical-field pulses are used in electroporation to encourage bacterial and other cell uptake of DNA and other macromolecules from the surrounding environment. The process by which bacteria absorb DNA from their surroundings is known as transformation.
What kind of sequencing of DNA use dideoxynucleotides as sequence terminators?
The only kind of DNA sequencing that makes use of chain termination and dideoxynucleotides is Sanger sequencing. Dideoxynucleotides are not used in Ion torrent or HTS sequencing, two forms of Next-Generation Sequencing.
Because RNA polymerase was never separated from the gene-mRNA complex, a transcription reaction is unable to be completed. What phase of transcription is this error most likely to have happened in?
Termination is the point in transcription where RNA polymerase is freed from the gene-mRNA complex. Although promoter region binding occurs during the transcription initiation stage, it is not thought of as a stand-alone stage.
Because of Meselson and Stahl's research, it is acknowledged that DNA replicates by:
DNA replicates, as the Meselson-Stahl experiment showed using a semi-conservative model. They were able to show that DNA preserves one original template strand when replicating into a unique DNA strand by utilizing the nitrogen isotope N-14.
A eukaryotic cell lacks spliceosomes by nature. The gene products that resulted would probably:
A spliceosome's function in a cell is to join the gene's exons after removing any extraneous introns. Alternative splicing would not be feasible in the absence of spliceosomes.