Final answer:
The correct statement about reverse transcriptase is (d) It synthesizes DNA from an RNA template. This enzyme is used by retroviruses to convert their RNA genome into DNA within a host cell, which is the reverse flow of genetic information compared to normal cellular processes.
Step-by-step explanation:
Of the statements provided, the correct one is (d): It synthesizes DNA from an RNA template. Reverse transcriptase is an enzyme that is crucial for the replication of retroviruses, such as HIV. It allows these viruses to convert their RNA genome into DNA inside a host cell. This RNA to DNA conversion is against the usual flow of genetic information in cells, which is typically from DNA to RNA, and hence the process is termed reverse transcription.
Once the reverse transcriptase synthesizes a DNA strand from the RNA template, this single-stranded DNA forms a double-stranded DNA molecule, also referred to as complementary DNA or cDNA. This cDNA is integrated into the host cell's genome and can then be transcribed to produce viral RNA, which will be used to form new virus particles. Reverse transcriptase is not associated with the conversion of DNA to RNA, is not solely found in prokaryotes, and does not play a direct role in RNA splicing.
Additionally, reverse transcriptase is now a valuable tool in genetic engineering and biomedical research. For example, in reverse transcriptase PCR (RT-PCR), reverse transcriptase is used to create cDNA from an RNA sample, which is then amplified by PCR for various applications including gene expression analysis.