Question

Describe how [3H]thymidine and autoradiography can be used to determine the length of the various periods of the cell cycle?

Answer 1

Tritium labelled thymidine is used to study the various lengths of the cell cycle because it has various advantages in the formation of the precursors of DNA. Although thymidine is not incorporated directly in the DNA synthesis pathway, it is incorporated by it's monophosphate form in the Synthesis or S phase of the nuclear DNA formation. The tritium labelled thymidine is used to pulse-label the growing cells and thus study the time required for the cell cycle to complete each of its steps and study the cycle via autoradiography. This is a much sensitive test hence is a good test to study the cell cycle phases lengths.