Question

What is a double thymidine block?

Answer 1

Double thymidine block:

1. During cell division, a cell crosses through various phases in order to get duplicated into two.
2. Three such phases in order are the G1, S, and G2 phases.
3. Thymidine is a chemical used during cell division that acts as an inhibitor of DNA synthesis.
4. This action arrests the cell at the G1 to S boundary just before DNA replication.
5. Another treatment with thymidine arrests all the cells at the start of the next phase i.e., the S phase.
6. This method is called double thymidine block.
7. This method is used to obtain synchronized cells all at a stage prior to the beginning of the S phase by treating the asynchronous cells with thymidine.