Sombat Singhakaew. Ultrastructure of male germ cells in the testis of abalone haliotis ovina gmelin . Master's Degree(Zoology). มหาวิทยาลัยเกษตรศาสตร์. : มหาวิทยาลัยเกษตรศาสตร์, 2001.
Ultrastructure of male germ cells in the testis of abalone haliotis ovina gmelin
Abstract:
Abalone are dioecious gastropod marine mollusk. The single gonad envelops hepatopancreas, and they form a large cone-shaped appendage called conical organ, wrapping around the right posterior margin of the shell muscle. The aims of this thesis were to study the histology and ultrastructural characteristics and pattern of chromatin condensation in the male germ cells of Haliotis ovina during spermatogenesis by light and transmission electron microscopy. Male germ cells could be classified into thirteen stages based on the cell size and the pattern of chromatin condensation: spermatogonium, five stages of primary spermatocyte (leptotene, zygotene, pachytene, diplotene and metaphase), secondary spermatocyte, five stages of spermatid (spermatid I, II, III, IV, V) and spermatozoa which comprised a head, containing a barrel-shaped nucleus and large conical acrosome, a midpiece of five mitochondria, a tail with 9+2 arrangement of microtubule.