DNA Replication and its significance Grade 12 Life Sciences Notes with Activities. On this page you will find DNA replication and its significance Grade 12 Life Sciences Notes under Nucleic acids, which includes revision activities with questions and answers to help grade 12 learners to prepare for their tests and exams.
Notes
DNAÂ replication takes place at interphase before mitosis or meiosis begins. DNA replication is the process during which a DNA molecule makes an exact copy (replica) of itself.
Steps of DNA replication:
- The double helix unwinds.
- Weak hydrogen bonds between nitrogenous bases break and two DNA strands unzip (separate).
- Each original DNA strand serves as a template on which its complement is built.
- Free nucleotides build a DNA strand onto each of the original two DNA strands by attaching to their complementary nitrogenous bases (A to T and C to G).
- This results in two identical DNA molecules. Each molecule consists of one original strand and one new strand.
Importance of DNA replication Grade 12
DNA replication is important because it:
- Doubles the genetic material so it can be shared between the resulting daughter cells during cell division.
- Results in the formation of identical daughter cells during mitosis.