A nucleic acid probe is a(n)
Group of answer choices
enzyme that locates a specific restriction site on RNA.
piece of radioactively labeled DNA that is used to locate a specific gene.
virus that transfers DNA to a recipient cell.
plasmid that recognizes a specific DNA sequence.
To determine the correct answer, let's break down each option and see which one aligns with the definition of a nucleic acid probe.
1. "Enzyme that locates a specific restriction site on RNA." - This option describes an enzyme that recognizes a specific site on RNA and does not align with the concept of a nucleic acid probe.
2. "Piece of radioactively labeled DNA that is used to locate a specific gene." - This option matches the definition of a nucleic acid probe. A nucleic acid probe is a short, single-stranded DNA molecule that is labeled (usually with a radioactive or fluorescent tag) and used to identify and bind to a complementary sequence in DNA or RNA.
3. "Virus that transfers DNA to a recipient cell." - This option refers to a viral vector, not a nucleic acid probe.
4. "Plasmid that recognizes a specific DNA sequence." - This option does not accurately describe a nucleic acid probe. A plasmid is a small, circular DNA molecule that can replicate independently of the host genome. Though plasmids can be engineered to recognize specific DNA sequences, they are not typically referred to as nucleic acid probes.
Based on the explanations above, the correct answer is a "piece of radioactively labeled DNA that is used to locate a specific gene." This definition best matches the concept of a nucleic acid probe.