Question
DNA are said to be polarized means?
Answers
GPT-4o mini
DNA is said to be polarized because it has inherent structural directionality, which is primarily due to the orientation of its sugar-phosphate backbone. This polarization is characterized by two distinct ends:
1. **5' End**: This end of the DNA strand has a free phosphate group attached to the fifth carbon of the sugar molecule (deoxyribose) in the backbone.
2. **3' End**: This end has a free hydroxyl group (-OH) attached to the third carbon of the sugar molecule.
Because of this difference in the chemical structure at either end, DNA strands are often described as having a 5' to 3' direction. This polarization is critical for several key biological processes, including:
- **DNA replication**: DNA polymerases can only synthesize new DNA strands in the 5' to 3' direction, meaning that they add nucleotides to the 3' end of the growing strand.
- **Transcription**: During RNA synthesis, RNA polymerase also synthesizes RNA in the 5' to 3' direction, using the DNA template strand in the 3' to 5' direction.
Thus, the polarized nature of DNA is essential for the accurate transmission and expression of genetic information.
1. **5' End**: This end of the DNA strand has a free phosphate group attached to the fifth carbon of the sugar molecule (deoxyribose) in the backbone.
2. **3' End**: This end has a free hydroxyl group (-OH) attached to the third carbon of the sugar molecule.
Because of this difference in the chemical structure at either end, DNA strands are often described as having a 5' to 3' direction. This polarization is critical for several key biological processes, including:
- **DNA replication**: DNA polymerases can only synthesize new DNA strands in the 5' to 3' direction, meaning that they add nucleotides to the 3' end of the growing strand.
- **Transcription**: During RNA synthesis, RNA polymerase also synthesizes RNA in the 5' to 3' direction, using the DNA template strand in the 3' to 5' direction.
Thus, the polarized nature of DNA is essential for the accurate transmission and expression of genetic information.