There are three types of DNA found in living cells. These are-
1. A-DNA: A-DNA is right-handed and double helix. It consists of 11 base pairs. The distance between their bases is 0.34 nanometers.
2. B-DNA: B-DNA is right-handed and double helix. It consists of 10 base pairs. The distance between their bases is 0.29 nanometers.
3. Z-DNA: Z-DNA is left-handed and double helix. Its chains are decorated in two curved positions.