About 40% of UK bioscience graduates opt to do postgraduate study for a PhD or Master's degree. This is partly because grants are more easily available in the Sciences for postgraduate study than in the Arts or Social Sciences. It should be remembered though that postgraduate study is not an easy option and research for a PhD will require dedication and determination to see things through over a period of 3 or more years.
It is becoming quite rare now for bioscience graduaets to enter a PhD without having done a Master's degree first.