EMBRYO BIOPSY & PREIMPLANTATION DIAGNOSIS (PGD) 1) A 7 cell embryo prepared for biopsy on culture day 3 2) A gentle acid solution is applied to the zona "shell" of the embryo, allowing access to the blastomeres contained within 3) The zona "shell" has been penetrated and opened. A single cell is selected for biopsy. 4) The selected cell is gently separated from it's neighbor cells and drawn into the biopsy instrument. Click Page 4 above for additional photos