Can anybody shed some light on this please?

[Frankiev]

https://youtu.be/7SnEFwshbA8?si=X9SaPc7elM10Qy7I

This is a long video - there are key timings in the video description.

[Bruce Taylor]

This is a single ciliate in distress from some trauma, such as failure of osmotic regulation and/or coverslip compression. In the early part of the video, a bleb (that is, a bulge in the plasma membrane) has already formed on one side of the cell. Blebbing is sometimes followed by complete separation of the bleb, and this almost occurs at 1:30; however, in this case cortical structures fail throughout, and the bleb is pulled back into the remains of the cell, which by this time has pretty much lost its cytoskeleton. The ciliate becomes a sphere of disorganized cytoplasm, loosely contained within the plasma membrane. Eventually, the membrane gives way, and the contents spill out.

[Frankiev]

Thanks very much Bruce Taylor. I’ll look into “ blebbing “