Antiparallel

Definition

Antiparallel describes the orientation of the two strands of DNA in which they run in opposite directions. One strand runs 5' to 3', and the other runs 3' to 5'.

5 Must Know Facts For Your Next Test

1. Antiparallel orientation is crucial for the replication and transcription processes in DNA.
2. The antiparallel arrangement allows base pairs to complement each other, ensuring accurate genetic information transfer.
3. DNA polymerases can only add nucleotides to the 3' end of a DNA strand, making antiparallelism essential for leading and lagging strand synthesis.
4. Hydrogen bonds between complementary bases (A-T and G-C) are stabilized by the antiparallel nature of DNA.
5. Antiparallel strands form a double helix structure, with one strand running from 5' to 3' and the other from 3' to 5'.

Review Questions

• Why is the antiparallel structure of DNA important for replication?
• How do base pairs interact in an antiparallel configuration?
• What role does antiparallel orientation play in the function of DNA polymerases?

Related terms

Complementary Base Pairing: The specific hydrogen bonding between adenine-thymine and guanine-cytosine.

Double Helix: The spiral shape formed by two complementary strands of DNA that are held together by hydrogen bonds.

DNA Polymerase: An enzyme that synthesizes new strands of DNA by adding nucleotides to an existing strand.