A Researcher Inserted DNA Fragments from an Organism into Plasmids

question 46

Multiple Choice

A researcher inserted DNA fragments from an organism into plasmids and introduced the modified plasmids into bacterial cells. Which of the following methods would be the most efficient means of identifying which clones contain a specific gene of interest?

• A) Use electrophoresis to identify plasmids containing an insert of the expected size.
• B) Use a labeled synthetic probe complementary to the gene sequence.
• C) Sequence the DNA of the plasmids from each isolate.
• D) Use a microarray to detect a transcript of the gene.
• E) Assay for activity of the gene product.

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Definitions:

Methyl Groups

An alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms - CH3. It can modify DNA molecules and affect gene expression when added to DNA sequences.

Euchromatic Regions

Areas of chromosomes that are less condensed during interphase, rich in gene activity and accessible for transcription.

Transcriptionally Active

Describing a state in which DNA is being actively copied into RNA by RNA polymerase, indicating active gene expression.

Genes

Sequences of DNA that code for proteins or functional RNA molecules, playing crucial roles in determining traits.