If I am not mistaken, I believe you are talking about baselining requireents, not backing them up.
In Quality Center, a project administrator can create baselines that provide ''snapshots'' of a project at different stages of development. In the Management module-Libraries tab, the administrator first creates a library, which specifies the root folders from which to import the data. The administrator then creates the actual baseline, which comprises the latest checked in versions of every asset included in the library. The administrator can also import and share entire baselines from other Quality Center projects. When a project reaches an important stage in the project lifecycle, the administrator can create a new baseline of the files in the library at that point. In Quality Center, these baselines can be viewed and compared in their entirety. Note that baselines are supported in Quality Center 10.00 Enterprise and Premier editions only. They are not supported in Quality Center Starter edition.