In what sense is Syringammina single-celled? For example, if it's true that all cells have membranes (is it?), then how do you identify its membrane? Or does unicellular simply mean that it has only one lipid bilayer (presuming --- since I don't know one way or the other --- that the crucial ingredient of any cell membrane is a lipid bilayer (is it?))
I'm not a biologist, so please excuse my possibly annoying question.