1 2 3 4

Blastomere Separation The cells were then separated into 3 100 ml beakers full of ASW. Care was taken so as not to add too much of the seawater-PABA solution. We then waited for the control culture to cleave for the first time. Then most of the water was poured from the first experimental culture. The beaker was gently filled with hypertonic seawater. The culture was then checked after 5 minutes to see whether osmotic shrinkage caused the cells to separate. The solution was replaced with additional hypertonic seawater if they had not separated. We waited 10 minutes after the cells show osmotic shrinkage. The hypertonic solution was poured off and replaced it with normal seawater. This was repeated. Steps 3-6 were repeated for the second experimental culture once the control group cleaved a third time. The embryos were allowed to develop and observed at different stages in their growth.