Mesosomes: Their role in the delimitation of the ascospore

Mesosomes of the ascus are described as the origin of the ascospore cell wall. We postulate an unfolding of the mesosomal structure as a mechanism for the formation of the double membrane system, which subsequently surrounds each nucleus. Cell wall material is probably synthesizedde novo at the expense of the double membrane system, since the mesosomes are especially suited for such a task.