⚙️ how
How does DNA copy itself before a cell divides?
Quick Answer
DNA is copied by enzymes that unzip the double helix and build matching new strands. This happens during the S phase of the cell cycle before division.
The Full Story
Before a cell divides, helicase opens the DNA double helix, and DNA polymerase builds new strands by matching bases according to A-T and C-G pairing. Because the process is semi-conservative, each new DNA molecule contains one original strand and one newly made strand. Additional enzymes proofread the new DNA and repair many mistakes. This high-fidelity copying is essential because the human genome contains about 3 billion base pairs.
Key Facts
1.Human DNA has about 3 billion base pairs
2.Copying happens in the S phase of the cell cycle
3.DNA polymerase and helicase are key enzymes
YouTube Angle
Suggested video title for this topic:
"The tiny molecular machinery that copies your entire genome"
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