Changes in DNA content and chromosome number during spermatogenesis in the gall midge Monarthropalpus buxi (Cecidomyiidae, Diptera)
1992
Jazdowska-Zagrodzinska, B. | Dallai, R. | Redi, C.A.
In this paper we analyze the course of spermatogenesis in Monarthropalpus buxi. The first meiotic division occurs without any chromosomes pairing. As a result one spermatocyte II appears from which two sperms originate, and one residual cell, which does not undergo any further division. We found variations in chromosome number and DNA content between germ line cells of different individuals. Such variations were observed in the spermatocytes I and II, and in the sperms. In contrast, the residual cells, which did not take part in further development, always had the same DNA content and constantly inherited 20 chromosomes: 4 constituting one haploid set of the somatic type (S chromosomes) and 16 of the germ line limited type (E chromosomes).
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